TorServers offers a way to donate bitcoins to help fund additional exit nodes. I was checking the address in blockchain and noticed only around 60 BTC have been donated so far.
I would think that the bitcoin community could do a little more to support Tor...
Here's a link to the page with bitcoin and litecoin donation addresses...though I highly recommend double checking the domain to make sure nothing funny is going on ...
http://www.torservers.net/donate.htmlI'm in no way affiliated, but do use Tor and think that's a pretty weak response from the bitcoin community.