I agree, and while it's not quite ready for a show HN yet.. I've been working on a quick side-project that allows people to send a 'thank you' to (github) open source committers.

I just completely agree that trying to motivate people who give huge amounts of time with small amounts of cash isn't a great idea. That said, it's good that there's a place for it (gittip etc.) should people want to.

Anyway, if you want to give feedback http://github.com/thankadeveloper/thankadeveloper and http://thankadeveloper.herokuapp.com (in the process of polishing, domain etc.).

I'm not sure if I'll ever really get the culture change in encouraging more "thanks" in the world, but it has been a fun little project getting up to speed on rails4, octokit etc.