Gmail feature you just can't live without.
andrewl-hn: I use Yahoo! Mail for historical reasons. I receive about 12-20 emails per day. Besides writing and reading emails I use Search - that's the only thing I really need. I also started using folders this year: the folder names are 2005, 2006, ... 2008 :) Current year emails are stored in inbox.
On average day I spend very little time on emails, though.I have a Gmail account, too, but I haven't found any Gmail-specific features I would use. Conversations or labels are neat and my spouse adores them. As for me I just don't care as long as my search box is working.