From Buzzflash. I saw a different version of this database, and was hoping to find it again, so I guess that $25 bucks I donated to Buzzflash was worth it! :)
As they so rightly point out, spending money with merchants/corporations that are "blue" might be a huge thing in an environment so evenly split. (What Fucking Man-Date?). It's not the most complete list, but it's pretty interesting.