A P2P app for the iPhone??

At first this sounds ludicrous... why on earth would you want to have a P2P app on your iPhone? Battery is already limited enough as it is... let alone drain it even more with constant downloading and uploading. And exactly how many TV shows can you fit onto the 8GB model?
Well its all made clear with iSlsk. This app is a pretty slick app.
If you can imagine the iTunes music store, but free, then thats a close approximation!
Of course, the developer makes the disclaimer that you should only download music that you've bought legally.
But it works astonishingly well. You can search for songs, and select which one you want, and what bitrate its at.
After downloading to \var\mobile\media\downloads folder, the app then gives you a choice of importing the song into the iPod app, and playing it there! Amazing.
One problem though, is keeping the song. Once synchronised to iTunes, the music is lost. You would need to SSH into the iPhone to copy it out, before re-importing into iTunes and then back to the iPhone. The iTunes music store is still one step ahead of the competition.... :)

EDIT: It does crash abit, but when you reconnect, it can resume from where it left off.
Also, as long as you don't import the songs into the iPod app immediately, and leave the songs in the /var/mobile/media/downloads section, you can sync with iTunes without issues.