No on 8* supporters have begun boycotts of business that contributed to/are owned by contributors to the Yes on 8 campaign. Now there are some serious issues with government-mandated disclosure of political donations, at least for those of us in the money = speech camp. But given the presence of these databases, shouldn't it be fairly straightforward to write a Firefox extension that crawls these databases and pops up a little window when you're on the website of a business that is associated with . . . uncongenial political views?
* For you non-Californians: Proposition 8 just outlawed gay marriage in California.