TFS Team Members Power Tool - see http://blogs.msdn.com/bharry/archive/2008/11/13/extending-the-new-tfs-team-members-power-tool.aspx or http://www.codeplex.com/tfscollab/SourceControl/ListDownloadableCommits.aspx for more on this.
Teamprise Remote Accelerator - I'm not as excited about this one - http://www.teamprise.com/products/accelerator - but its good in case the TFS server is ever super-widely used.
System Center 2007 Management Pack for TFS 2008 - great for monitoring uptime and problems with the TFS server(s) - http://blogs.msdn.com/granth/archive/2008/11/26/tfs-management-pack-for-system-center-operations-manager-2007-shipped.aspx
TFS to TFS Migration Tool - it comes with a lot of disclaimers on when you should not use it - http://www.codeplex.com/tfstotfsmigration
TFS Working On - the perfect system tray tool for tracking which task you are presenty working on - http://www.codeplex.com/TFSWorkingOn