If you have worked much with WSS and the many XML definition files that accompany it you will no doubt be generating a lot of guids. The "Tools|Create GUID" can be a bit cumbersome so I searched for an alternative and couldn't find one. So I wrote a simple GUID insert AddIn that adds three links to your editor context menu to insert guids in different formats. First a standard guid; "6D7C589A-DDBB-4B01-BCEE-6F921885F942", second an undecorated guid; "AFCE87A3021C4BF7A51078DFA1F73995" (Good for content type ID's), and third a "registry" guid; "{0E0057DF-B8EC-44E3-A9AA-3EDBFEA7025B}". The setup installs the source as well if you want to modify it.

Visual Studio 2005

Installer: InstallInsertGUIDAddin.EXE (288.28 KB)

Visual Studio 2008

Installer: InstallInsertGUIDAddin2008.EXE (234.92 KB)
Source: InsertGUIDAddinSource2008.zip (101.51 KB)