Four big things for me: 1) Offline copies: Either because I have no internet access or the webmail provider is down. For my company e-mail "Google is down" or

Four big things for me: 1) Offline copies: Either because I have no internet access or the webmail provider is down. For my company e-mail "Google is down" or "I can't get online" is just not a good enough excuse when such an easy solution exists. Even if you primarily use webmail I would highly suggest mirroring a local copy via IMAP if you're dealing with important stuff. 2) I like being able to segregate my mail into its own space. I maximize my mail client full screen and have other windows on my second display such as individual messages or notes, address book, calendar, etc. I find this to be more appealing than opening half a dozen browser windows and clicking through different sections of GMail. 3) Nothing beats the performance of a local store. My IMAP server keeps a full backup so any one client losing its local copy isn't a problem. Searches are instant in Apple Mail, I can bounce between different folders/messages with no penalty waiting for another GMail page to load. 4) No distractions. When I have to sit down and pound through lots of e-mail being in a browser makes me less productive.