Accessories. Peripherals. Add-ons. Are they the perfectly designed extensions to your favorite games consoles that they're marketed as? Usually, no. More often than not, they're badly designed, poorly constructed, and rushed.

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This isn't just limited to the home market, either. There are plenty of add-ons for your favorite handheld consoles and a bunch of them are just downright weird. Some are awful, some are useful, and some are completely pointless but they all have one thing in common; they'll leave you scratching your head, wondering why they exist.

Unsurprisingly, given the fact that they've dominated the market practically since its inception, the majority of these are for Nintendo consoles. Good job Nintendo!

10 The Car Adapter & Travel Pack for Nintendo's Wii

Whilst Nintendo's popular Wii console was a smash hit, it was never intended to be a portable device. "But I want to play Wii bowling on the go!" we hear you cry! Well, your prayers have been answered with this handy car adapter and travel kit.

Just plug the console into your car's power port using the handy car adapter (remember when this socket was just for lighting cigarettes?), insert your Wii console into the stylish travel kit - which includes a monitor and carry case - then mount that to the back of one of the front car seats.

It's a perfect solution and you'll be bowling strikes, executing TKOs, and slicing up fruit like a ninja in no time at all.

Just make sure you keep a firm grip on that Wiimote...

9 The Pocket Sonar For Nintendo's Game Boy

Picture the scene... you're out on the lake, fishing rod in hand, with an eager line out, desperate to catch something, anything... but no joy, not a single measly bite. You move to a different location, then again and again but still no luck! It's utterly hopeless.

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If only you'd remembered that back in 1998, only in Japan, Bandai released the Pocket Sonar for the original Game Boy...you could have been accurately tracking the movement of your aquatic prey at up to 20 meters depth.

And hey, if you still couldn't catch anything, at least you could have played the fishing game that came with the Sonar or even Tetris...

Much more fun than being stuck out on a lake not catching fish.

8 The Hands-Free Stand For Nintendo's Switch

Being left with aching wrists and forearms from holding your handheld console of choice aloft for hours on end is a common complaint amongst gamers. We've all been there and it's an irritating barrier to, you know, carrying on with your session.

For Nintendo Switch fans, however, that particular problem is now solved with this stylish hands-free kit which transfers the burden to the back of your neck, effortlessly suspending your console at the perfect angle for pain-free gaming. You can even use a pro controller on the go instead of the joy-cons.

The hands-free kit provides pain-free gaming for your arms at least, but your neck might not thank you for this one. Neck pain aside, you'll look like a trendy bionic person, so there is that.

7 The Solar Gear For SEGA's Game Gear

The Game Gear was notorious for its poor battery life of 2-3 hours on 6AA batteries. It was so notorious, that many gamers took to playing it on their sofa using the AC adapter (sold separately).

So what's a natural solution to rubbish battery life on the go? A solar charger of course. Enter the Solar Gear Rechargeable Solar Power Pack, a peripheral so rare that there's practically no information available on the internet, but it most certainly exists.

The device is essentially a cradle and rechargeable battery for the Game Gear with a large solar panel on the rear which in theory will provide unlimited power from the sun (if you live in a sunny country of course).

Yes, it does work, which you can see from this video, but portable solar chargers are pretty unreliable, even now, let alone back in 1994...

6 The Didget Glucose System For Nintendo's DS

A bizarre add-on with an important purpose. This blood glucose meter developed by Bayer HealthCare was designed to remind children to check their blood sugar levels. The device comes with several minigames that reward players for checking their blood sugar levels regularly.

It's a weird but clever idea, as children are probably much more likely to carry around a device that connects to their favorite gaming device and is associated with something they enjoy, rather than with a health burden.

Diabetes has never been so much fun...

5 The Band Hero Drum & Guitar Grips For Nintendo's DS

Remember Guitar Hero? Of course you do. What about Band Hero, the one where you could sing and play the drums too? You know, it had a massive drum kit peripheral? Anyway, they adapted it for the Nintendo DS. Whose dumb idea was that?

Of course, tapping notes out on a touchscreen isn't nearly as fun or cool as clicking a plastic guitar or bashing a plastic drum kit, so two peripherals were developed - the drum and the guitar grip.

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The drum grip fitted overlayed some rubbery drum pads on the controls and the guitar grip let you hold the DS in the palm of your hand and click buttons with your fingertips...

Unsurprisingly, they are both terrible.

4 The Sewing Machine For Nintendo's Game Boy Colour

No this is not a joke, there is genuinely a sewing machine add-on for the Game Boy Colour. Be honest, if asked to come up with an unusual concept for a Game Boy peripheral, never in a million years would you even consider a sewing machine.

So why even make such a seemingly bizarre device? Well, in truth it's just a cheap way of developing a digital interface to allow for the automated sewing of prescribed patterns and designs.

The sewing machine itself is nothing special and just has a digital cable connection to the Game Boy Colour which is then used to control what is sewn.

Embroidery has never been so much fun...

3 The WonderWave For Bandai's Wonderswan

Most of us will have heard of the Game Boy, the PS Vita, and even the Game Gear, but the Wonderswan? What is a Wonderswan? Well, it's a handheld gaming console released in 1999 by Bandai and released solely in Japan.

The console was ultimately discontinued in 2003 but is still highly regarded amongst those in the know.

The WonderWave is an add-on that allows the transfer of data between the Wonderswan and Sony's PocketStation...wait, what? That's right, the Pocketstation, a rare add-on for the original PlayStation home console and yep, you guessed it, only released in Japan.

The WonderWave - for when you absolutely have to transfer game data between two rare and obsolete consoles...

2 The Play-Yan For Nintendo's Game Boy Advance

If you ever wanted to turn your Game Boy Advance or Nintendo DS into an MP3 and video player, then the Play-Yan is the perfect accessory for you.

It's essentially a GBA cartridge with a headphone jack and standard SD card slot which allows audio and video files to be played on the screen of your favorite console. It also comes with several pre-installed minigames.

Unfortunately, for original GBA fans, the Play-Yan draws a lot of power and quickly burns through the console's batteries. If that wasn't enough, the low-def screen isn't exactly suited to viewing video files in high quality and if you want to listen to music while playing your favorite GBA games, you'll need a separate MP3 player since the Play-Yan uses the cartridge slot.

Unless you want to use it as a dedicated audio or video player, for which there were many better options at the time, the Play-Yan seems somewhat redundant.

1 The "Accessories (Which Are Sold Separately)" For Sony's PS Vita

Sony's original PS Vita (the 1000 model) has an accessory port, referred to specifically in the user manual as an "Accessory Port for connecting accessories (which are sold separately)."

That's all well and good until you realize that not a single accessory was released using this port and it was removed in a hardware revision later in the console's lifetime.

So, what were these mysterious accessories? Nobody really knows for sure but some say it's simply for mass data transfer and development testing, some argue it's for a rumored backward compatibility drive for the PSP's UMD discs, others are certain it's for video output to a TV and some even say it's the key to opening the Chamber of Secrets...well maybe not that last one...

An accessory that doesn't actually exist and manifests itself only in the speculation of online obsessives? It doesn't get much weirder than that.

NEXT: 10 Weird Ways To Play Portable Video Games On Your TV (Before The Switch)