Suggestion: pay him by Mass Payment. You end up kicking in $0.50 in paypal fees, he doesn't have to pay to receive. It ends up that more of your donation reaches him net (if you donate above, let's see, $7.25 or so).
You'll need to save a text file. I think you guys can probably manage, but to make it copy/paste easy:
firstname.lastname@example.org (tab) 25.00 (tab) USD (tab) winsocks_rocked (tab) This is a totally optional comment.
Thanks for Winsock, by the way. You saved me hours of frustration when I was trying to get Compuserve and Warcraft 2 to work together, back in middle school. Crikey I feel old.