Fortunately my host offers webmail access to email, which is a great way to get to your mail when away from your computer. It is also a great way to be able to send when your company turns off Port 25. ;(
Squirrelmail, which is the software I have access to, refreshes on a nice short interval and can even notify me of new messages with a sound or a simple change in the name of the tab I am leaving open in Safari. While not as good as any POP or IMAP client you might have, it gets the job done and plays within the rules at work.
Whoa – one cool thing I just noticed as I was clearing out some spam is that you can block receipt requests when you open or check messages.