I'd be really curious to hear Basecamp's opinion on Gumroad, and how they'd compare and contrast their own experience with it (Basecamp is the new name of 37signals).
Basecamp's CEO Jason Fried actually shared his thoughts in a tweet:
"Good read on how Gumroad experiments with work, structure, hiring, and compensation. Re: part time... Little known fact: I hired @dhh
quarter-time (10 hours a week) to build Basecamp way back in 2003. That's all he had, and we made it work."