Google "Even More" - http://www.google.com/intl/en/options/
Try some of these...
Google Almanac - A Google Site Created by GCTs (Kyle Brumbaugh, Jerome Burg, Cheryl Davis, & Kathleen Ferenz) for the GTA
Google Hacks - A good reference book. The first half or so includes some great tips... the rest gets a bit technical
Googlepedia - Another good reference book to use when teaching particular applications
Google Earth Lessons - A bunch of lesson plans
Google Apps Tutorial - A video on Google's site about Apps
Google Lit Trips - Great stories, seen geographically, by Jerome Burg
Google Channels on YouTube - All sorts of videos with information on various Google tools
Google Groups - Create simple communities connected via e-mail with shared files and more
Take a quick tour of Google Groups: http://groups.google.com/intl/en/googlegroups/tour3/index.html#?lnk=hptt
Google Calendar - Share calendars with family/friends/colleagues
Take a quick tour of Google Calendar: http://www.google.com/intl/en/googlecalendar/tour.html
The page for Google Reader
Reader is an RSS system for having changes to your favorite sites and pages reported to your e-mail. The video below explains RSS.
The page for iGoogle
Create a personalized home page with all manner of widgets/gadgets/tools, from your weather, to your mail and docs, to the thought of the day, to the online stopwatch. You can also customize the look of the page, with themes that change by the hour.
Creating Your Own Start Page
The Tool: http://www.igoogle.com
The Crib Sheet: http://sites.google.com/site/gtaresources/files/Crib_iGoogle.pdf?attredirects=0