This is a web site that I accidentally came across a while back, don't remember how, but it's called 'Click to Give'. This costs absolutely nothing and helps through sponsors when you 'click' on the cause or charity.
Please take the time to read the very detailed page on how this site works...
Click to Give - How This Site Works (http://clicktogive.com/How-This-Site-Works.aspx - broken link)
You get 'rewarded' with points to accumulate, redeemable for 'Click to Give' site merchandise. We all spend quite a bit of time on here and this only takes a few minutes and really does help. The site is VERY detailed with information.
You can also sign up for daily reminders, which I highly recommend. I missed several 'clicking' days trying to remember on my own.