Google Desktop Developer Group - join
The Google Desktop Developer group is an unmoderated forum for developers to have discussions about the Google Desktop APIs.
Low activity, 4657 members, restricted

Google Desktop Help (Enterprise Edition) - join
Welcome to the Google Desktop for Enterprise Help Group, where you'll find answers from expert users and even our own Google Desktop for Enterprise Guide (a Google employee). If your specific question isn't answered here already, you can post it and let the experts weigh in. First, read our charter at http://services.google.com/desktop-enterprise/help-charter
1462 members, restricted

Google-Firefox-Extensions - join
This is a discussion forum where you can exchange information and discuss Google-developed extensions for the Mozilla Firefox browser.
Low activity, 5027 members, restricted

Google Calendar Help (Archived) - join
Welcome to the Google Calendar Help Forum Archive! Please note that this forum is only an archive and you can no longer post questions here. Please see our new forum here: http://www.google.com/support/forum/p/Calendar?hl=en
44698 members, restricted

Gmail-Users - join
Talk about Gmail, good or bad.
Low activity, 17936 members, moderated, restricted

Google Labs - Web Accelerator - join
This is a discussion forum where you can exchange information with other Google Web Accelerator users.
Low activity, 2571 members, restricted

Google Labs - Notebook - join
This is a discussion forum where you can exchange information with other Google Notebook users.
Low activity, 2968 members, restricted