Whats the best P2P program to use?

[Meiosis]

For music I recommend Blubster. Pretty good speeds, only problem I came across was a router problem.

For everything else, use bitorrent.
I made a couple of game video clips and released it with bitorrent, it's the best way to spread files while making sure your friends share them as well. It's a faster way to make sure people get the files in a faster amount of time.