"We've added an option to Settings to always use https. If you don't regularly log in via unencrypted wireless connections at coffee shops or airports or college dorms, then you might not need this additional layer of security. But if you want to always use https, then this setting makes it super easy. Whenever you forget to type https://mail.google.com, we'll add the https for you. If you already have the https URL bookmarked, using this setting will ensure you access your account via https even when you don't use your bookmark. Any http link to Gmail (for example, the one at the top of Google.com) will be automatically redirected to https.", says the Gmail blog.

Google is in the process of rolling this feature out to all Gmail and Google Apps users, so check back in your Settings menu if you don't see it right away. In the meantime, you can go directly to https://mail.google.com right now if you're nervous about snoops. (Or https://mail.google.com/a/example.com if your Google Apps domain is example.com.) Google Apps Premier Edition admins will also be able to select SSL connections for their users via a new preference in the control panel we'll be rolling out shortly.