I try to buy products that are: non-toxic, eco-friendly, organic, local, union-made (or at least fair-trade.)

But sometimes all I can find are major brands.

I just found this cool site: Climate Counts.
The site measures the impact on global warming that major brands have.
I was surprised to see that Unilever scored fairly well.
So when I can’t find organic or locally-made mayo, I’ll buy Hellman’s instead of Kraft (Kraft scored pretty bad.)

Combined with my favorite shopping review site, Responsible Shopper (which grades companies on environmental impact, fair-trade practices, ethics, etc.), I know that I’m not supporting companies whose practices are against my beliefs.

Remember, the US is a consumer culture, and what we do and do not buy influences the decision makers more than what we say.
Talking the talk is fine, but walking the walk is more important.