Regretably I actually sent an angry email to Bit-Blot because Id paid for Aquaria and then couldn't download it. An alternate link was provided almost immediately which had me blushing and wishing I could unsend my email 
I've sent several e-mails out to various indy game makers with compliments/comments (when they were very little known), questions(game problems/bad glitches), or... Can't remember the other one. Either way, they all replied by the next day and were way too kind, it's a nice change from the hotlines or websites like EA.