Ask HN: Anyone having success with offering an affiliate program?

I'm curious if anyone has implemented an affiliate program for their web app business and seen a good payoff. I remember Joel saying they spent a lot of time and money on getting an affiliate program together for FogBugz and it flopped. I've also been watching the affiliate program 37signals has/had?

https://affiliates.37signals.com/affiliate/

The affiliate area never got a new design with the rest of their sites which seems to point to it not being very lucrative to get new people to signup. And the whole not accepting new members might point to that too.

Anyone have any stories out there good or bad with fooling around with getting an affiliate program up and running? I've been pondering trying one out (for http://tgethr.com/), but the work and admin involved seem daunting to even give it a small try.

I've thought about using something like Shareasale to try it. Or even Clickbank. Clickbank is loaded typically with get rich quick schemes but they at least make affiliate management pretty easy. However Clickbank isn't all that well slated for web app subscription tiering.