Yeah, there's a ton of amateur wedding videographers using the iRiver 700 and 800 series super-portable mp3 players as substitutes for wireless lavs. I believe they can handle line or mic level inputs, have adjustable levels (not gain, probably attenuation), and encode to mp3 on the fly up to decent bit rates. Don't quote me on all of that, especially mic in, but I'm pretty sure. Also, my wife has a Creative Nano which is iPod shuffle-like small, but it only takes line-in and has no level control. Anyway, just some more ideas...