With just $16k let to go in the match I'm reminded that silly gimmicks don't usually work for this kind of fundraising. In the past I thought of ridiculous ideas - a letter to a loved one, thanking them for the time that the donor spends on free software (like as a holiday present!), performing a new software freedom song,...
We once gave away a bottle of wine signed by wine developers! (they're mostly beer drinkers though)
What is the silliest or coolest thank you gift you could imagine?