WMP Tag Support Extender
WMPTSE (or Windows Media Player Tag Support Extender) is the a plug-in to Windows Media Player to allow more tags support than ID3 within the player.
It support version 9.x, 10.x and 11.0 of Windows Media Player.
The current version (1.1.1) support Vorbis comment, APEv2 and FLAC
Supported Formats
Additional formats may be supported through a plug-in API (known as WMPTSE API)
Extensibility
WMPTSE provide options to add tagging based on file extension.
This permit exotic but usefull things as AC3 DTS files tagging. Or less usefull things as .txt, JPEG file tagging and more.
Price
The sofware is free.