EC2 is overkill for leeching (or even seeding) a few torrents. If you want more bandwidth just find some crappy $5 VPS server somewhere (lowendbox reviews a steady stream of cheap hosting) and install torrentflux.
The entire point of having a VPS is that you're guaranteed a slice of the server to do what you want. If your provider is somehow monitoring your processes, sniffing your traffic, and setting restrictions on your applications, then I would find another one.
Amazon Web Services does not ban BitTorrent or IRC. They actually support BT as an official delivery method from S3.
http://docs.amazonwebservices.com/AmazonS3/2006-03-01/index....
I took that to include copyrighted data, including Battlestar Galactica episodes.