The current project I'm working on involves managing and launching a lot of http requests to different web service api's, and gevent really is the best thing since sliced bread.

Things like rate limiting (gevent can monkey patch time.sleep), error handling, and scaling to a large number of concurrent connections (see gevent.pool.Pool) have been added to my app with surprisingly little increase in code complexity. The fact that you write your code as if it was synchronous makes it so much easier to maintain. I don't have to find my way through callback spaghetti. I also find asynchronous much easier to grok than threading (and it's also more lightweight)