The other day I read about how Go Daddy supports SOPA (and loves Microsoft and kills elephants !). Since there has been a massive move of domains out of GoDaddy, including Wikipedia (still at GoDaddy as I write, c'mon Jimmy, it's been 5 days now!).
If you actually use GoDaddy you can pledge to boycott GoDaddy.. . and/or you could just up and leave them, I mean who registers a domain with a company whose name is "Go Daddy" ?
Important note, if you leave, be careful where you go as there are many GoDaddy re-sellers out there.. Just go to Gandi.net or EasyDNS, they both openly oppose SOPA and aren't just doing it for marketing's sake.