After reading Kottke's post about indieKarma, I've signed up and dropped the code into my blog template in a crass and bald-faced move to monetize my blog. We'll see what happens - and let me know if the thing becomes too annoying or whatnot. It seems like an interesting concept.
Just thinking further about this thing - it would be neat if they could eventually include some further features to exploit the cross-blog placement of that JS include. Maybe some metrics and reporting in general, maybe some more blog-shiny whizbangs, maybe a small indicator of how many other indieKarma-capable visitors hit the site in the last 5 minutes.