Anybody who has a gmail or Yahoo e-mail address can access their e-mail using a desktop client with POP support. Although I guess a majority prefer the web interface for its convenience, I think a mail client is extremely useful and makes e-mail management a lot more sophisticated - and you get the best of both worlds in this case (web access as well as client access). The main reason I switched to a mail client is because gmail's new web interface is far too slow and unwieldy.

I use KMail in my Debian box, since it's integrated with the KDE PIM module as well as KDE's address book.

Here are some reasons you might want to switch to client-based e-mail access:

• Convenient way to read and compose messages while off-line and the ability to queue up messages to be sent at one particular point of time.
• Since messages are downloaded to your hard disk, you have a natural back-up for your important mail.
• Mail clients allow you to access multiple e-mail accounts within one single, unified interface. This facility also allows you to easily preserve old e-mail from previous accounts while switching to a new one.
• Transferring or backing up e-mail is as convenient as copying or archiving a directory.
• Since mail clients are desktop applications, they are responsive and stable whereas accessing webmail depends on the speed of the internet connection. Also a lot of webmail interfaces are bloated and slow (examples of this are the new gmail/Yahoo interfaces which really chokes the browser at times)
• Using a mail client feels more professional and business-like.