You can configure GMail so that when you use it it always connects securely over an SSL connection (the "always use https" setting). The one problem with this is when you do this it will break the GMail Notifier. If you don't use GMail Notifier this is no big deal. But if you do use it, you probably know it's really convenient and you don't want to lose it.

Google has created a registry patch that allow the GMail Notifier to work even when you set your settings to require the use of https. Go to this page http://mail.google.com/support/bin/answer.py?hl=en&answer=9429 and they explain everything you need to do to get the Notifier working when you are using GMail over SSL.