P2P Responsible for Upwards of 90% of Net Traffic

According to a recent article at Ars Technica:

P2P traffic is dominating the Internet these days, according to a new survey from ipoque, a German traffic management and analysis firm. ipoque's "preliminary results" show that P2P applications account from anywhere between 50 percent and 90 percent of all Internet traffic. The final survey results are not yet available and will presented at the Emerging Technology Conference at MIT later this month.

Supplanting eDonkey as leader of the pack is BitTorrent (see the 2006 ipoque report). While it is now available in many different implementations, BitTorrent was originally implemented in Python. You can learn more about peer-to-peer networking in "Peer-to-Peer Networking: An Overview".