There is only one file type that uses the .TMBUNDLE extension:
TextMate Bundle File
Add-on file used by TextMate, a source code text editor for Mac OS X; contains a bundle of resources that add new features to the software; commonly used for adding source code editing support for new programming languages.
TextMate bundles used for language support can be used for enabling syntax highlighting, tab triggers, code completion, and hotkey shortcuts.
Several TMBUNDLE files are included with the TextMate installation. They are located in the application bundle file within the /Contents/Shared Support/Bundles/ directory. New bundles can be created using the Bundle Editor, which can be opened by selecting in the software.
Updated: May 31, 2011