"I'm making a difference" is the name of a new initiative from Windows Live Messenger to promote their Instant Messenger client platform at the same time that they share "a portion of" the ad revenue with some of the big fundraising organizations.
When I wrote some time ago about the long tail of philantropy, I describe something very similar to this implementation MS Live is now launching.
The main differences between what I had in mind and what MS Live did are:
1. I was thinking in using an universal IM client. Something like Pidgin 2.0 that is open source and could be modified to hold google ad sense for instance.
2. Almost 100% of the revenue in such an effort would go directly to the beneffiting organizations, just maybe leaving a minimum operative budget for the running of the program.
3. The organizations I had in mind were more diverse and not necesarily as big as the ones they choose.
1 and 2 would make a whole lot difference, but still this MS Live is a nice initiative.