Let's say you were approached to work for a big name company who is working on a lot of really amazing high tech products. Their current employees seem intelligent, motivated, friendly and happy to work there. The work environment looks sweet. The only thing making you have second thoughts is that some of their actions (such as pushing for lower corporate taxes) don't exactly mesh with your ethics. Sure, they're not anti-competitive; they even do a lot of open source; but more than a few of their actions have come under fire as unethical. Would you work for them? Would an employment boycott be effective?
Just for the record, no, I have not received an offer yet; I don't presume that I'm a shoe-in (they have a very high false positive rate). I'm putting this out early to get as many responses as I can. I currently work for the US DoD, which some would see as extremely unethical. If you can't figure out from what I've told you so far (and my comment history) which company this is, you probably shouldn't reply to this, but I'll take all the input I can get.