We have similar situations! When I was a grad student I decided I'd donate 10% of my gross income to charity once I got a job after graduation. I was also convinced by Peter Singer's work.
At the beginning of this financial year I donated $6,000 to Against Malaria Foundation. I'd allocated about 50 hours for research to find the best charity, but once I found GiveWell I only spent a few more hours looking further.
My initial plan was to donate to GiveWell directly, but I emailed and asked about their tax status. I told them that if they weren't tax deductible in Australia, I'd give them 30% less than I could give to their top-rated charity that was deductible (since that's what I'd get back from the deduction). They told me to donate directly to AMF, as they were adequately funded.
Later AMF emailed me back and apologised, saying they actually aren't tax deductible for individuals at the moment. I told them they then needed to give me back $1,800, or they could give it all back and I'd wait until they sorted the problem out. They chose the latter; I guess they expect it won't take long.
So currently I still haven't made a donation. If it gets to June and I still haven't heard from them, I'm not sure what I'll do. I might have to find the best tax-deductible charity and decide whether it's <30% less efficient than AMF.
When I was a graduate student at the University of Notre Dame, I received a monthly living stipend of roughly $1,600. I decided to commit to giving ~10% of it to charity, and I had read in Peter Singer's book The Life You Can Save that one of the most efficient charities out there was Population Services International (PSI). Singer reported that GiveWell, a leading charity rating organization, had estimated that PSI's efforts saved lives at a cost of $650-$1000 each (pp. 88-89). So, I set up a recurring monthly donation of $160 to PSI, and kept it up for 15 months, for a total donation of $2,400.
I've been meaning to post the above information publicly for awhile, but was pushed over the edge by reading one of Eliezer's posts from a couple years back, Why Our Kind Can't Cooperate:
Since Eliezer's post is about rationalists, he stresses the issue of what arguments people voice. However, we know that just telling other people that you've given to charity makes them more likely to give. This is a point that Singer himself has emphasized.
I propose a thread for people to publicize their charitable donations. In light of the above, I'm especially interested to hear from people who've donated to the Singularity Institute for Artificial Intelligence. Once I acquire a regular source of income again in March, I intend to continue to primarily direct my charitable giving towards PSI, but maybe someone in this thread will persuade me to start giving to the Singularity Institute.