[icebraining]

Torrents are good design. They force everyone who downloads to also upload.

Nope: http://bitthief.ethz.ch/

Bittorrent is just a good example of the "defaults matter" guideline.

By the way, I don't think relays are the problem. Exit nodes are, and you can't force everyone to run one, since it would literally lead to detentions and even prison sentences.