There is a guy in my office who loves his USB ports. We call him the wizard because he walks around with a big hat, an intricately carved walking stick, and a belt with fancy tassels. He is eccentric and nerdy beyond compare. He is the kind of person I envision when I think about all of the stupid USB gadgets in the world and the people who use them.
Here are a couple of the gadgets that you can find on his desk:
Snake fan:

Conceptually, this is not a stupid idea, but when you hear the hideous noise this thing makes, you wonder what the point is.
Beverage Cooler:

That's right. You put your cup on top of this and it keeps it chilled. In theory. We stole it from his desk while he was out of the office and tried it out for a day. This thing couldn't keep Dick Cheney's heart cold.
Those are just the ones I could get pictures of, but it got me thinking about all the other terrible USB devices out there. I then scoured the internet for the worst and this is what I came up with:
USB Mini Fridge:

If the beverage cooler wasn't good enough, there is a mini fridge to keep your Diet Coke cool while you sit on your ass all day.
USB Lighter:

It takes a special kind of dweeb to light his cigarettes with a device plugged into a computer.
USB Ashtray:

It takes an even more special kind of dweeb to use this thing. Parents, I guarantee that if your kids saw you using one of these, they wouldn't think smoking was cool.
USB Knee Warmers:

I'm worried about the people who actually own these. I'm also curious about the procedure of getting up and going to the restroom. Do you slip out of the knee pads or do you walk to the loo with USB cables dangling from your legs?
USB Massage Ball:

I have a good marketing idea for this. Get some lesser-known fast food chain to package this with their kids meal. It looks cheap and simple enough, not to mention right on par with the shady toys you always see from those kinds. The uproar will spur sales like nothing else.
USB Infrared Pain Soother:

Technology and new age medicine working together in perfect harmony. After finding this, I immediately searched to see if there was a USB Chi Balancer. No such luck.
USB Toothbrush:

Dumbfounding concepts like these illicit a very narrow range of responses. If I told you what I am thinking, there's a good chance you're thinking the same exact thing.
USB Amber Alert Child Identification Kit:

For the paranoid and incompetent parents among us. No snarky comment I could make is worthy of the hilarious absurdity of this device. Step 1) Simply use the tools provided on this USB drive to store all the information about your kid on an easily misplaced/re-appropriated gadget. Step 2) Gain piece of mind and reassurance... of WHAT?!?
USB Potpourri:

Look out, Glade. I wanna see the combo of lighter, ashtray and this genius device all plugged into the same USB hub.
Through this search, I was unable to find the holy grail of useless USB devices. Sure, I found a USB aquarium. A USB hamster wheel. A USB pole dancer. Even a USB teddy bear. But there is one device that tops everything you've seen here. It is a USB mouse nudger. It nudges your mouse every 5 minutes to cancel out your screen saver. Genius!