Music is best when its blasting loudly out of speakers and irritating everyone else who's not into it. That's why boomboxes are so awesome. Except carrying portable speakers is a hassle you'd rather not put up with. Here's a possible compromise: the Vibroy Portable Vibration Speaker.
It's not actually a set of speakers. Instead, you can slap the gadget onto any object in the vicinity, hook it up to your iPod, and turn that object into a temporary speaker. It can supposedly work on most anything, including your adjustable laptop desk, that empty cooler box, those Warhammer beer steins and whatever else you can hook it up to.
The Vibroy is a pocket-sized gadget that turns everyday objects into makeshift speakers. Just hook up the tethered sticker part to any item in your reach (it can attach to any surface), turn on your music player and the sound will literally come out of your chosen object. Like magic and shit. It requires two AA batteries to operate, but it can also be plugged up to a USB port for power when you're at your desk.
With a 1W output and 78db noise level, we doubt this will make for the best sound. Then again, if you're just trying to piss off everyone in the train by playing Gucci Gucci nonstop, just stick this to a post and play away. And make sure you sing along with the part about swag coming out your ovaries. That's always fun.
Thinkgeek has the Vibroy Portable Vibration Speaker available now, priced at $29.99.