Most Google services are now avaible over encrypted ssl connections. Google Apps now offers the option to enforce ssl for most of it’s services. Here is the overview:

Email - Yes. Calendar - Yes. Docs - Yes. Sites - Yes. Chat - Yes. SSL supports Chat in Gmail. The Google Talk Client is always over a secure connection (TLS). Video - Not available. Start Page - Not available. This includes start page gadgets for email, chat, calendar, and docs account.

To enable SSL enforcement in Google Apps services login as an Administrative user for your Google Apps hosted domain, click on Domain Settings tab and check SSL checkbox.