I got a Play-Yan Micro a few years back when I didn't have an MP3 player. Since then I've gotten a 120GB Zune, so I have no use for the Play-Yan anymore, but I hate to see it sit there and gather dust. If anyone wants it, I'd be willing to let it go for relatively cheap. I originally got it for around $90, so I think a fair price would be around $30, but I'd be willing to negotiate.
For anyone who doesn't know, the Play Yan was a cartridge accessory made by Nintendo which plugs into your GBA or DS like a regular game. However, it has an SD card slot and a headphones jack on it as well. So in other words, it turns your DS and GBA into a media player. It can play both mp3 files and a couple of movie files as well, though I forget which. Just add the files from your computer onto the SD card and you're all set. It even has a neat little retro Super Mario Bros. theme to the menus.
If you're into the whole geek-chic kinda style, then this is right up your alley. Especially when you use it in a Game Boy Micro. It's pretty nifty looking and works great for what it does, but I just have no use for it anymore. If anyone wants it, I'll also throw in a free pair of headphones as well.