If you buy a lot at Amazon.com you can raise money for just about any 501(c)3 charity by using http://smile.amazon.com instead of http://amazon.com.

Amazon donates .01% of your purchases to any IR recognized charity with an EIN. I recommend the one I work for, Connor's House, where we help NJ families caring for children with life-shortening conditions.

And it'd be great if LifeHacker were to link using the Amazon Smile links instead of the plain ones. You still get referral fees, and it will help out lots of different charities.