TFS is in most cases very wonderfull. But if you have projects, which will also be used “outside” of the TFS environment (for example in an other subsidary without TFS access), then it has one disadvantage:
The comments for every check-in is only stored in the TFS version history.

While this is enough, if you always have access to the TFS. But if you work without TFS, then it would be helpfull if these comments are also included in the source-file (like in the old days, when we were using cvs (a feature called keyword-substitution)

I searched the web for any plugin for TFS which has almost the same features… but could not find any plugin….

So I wrote my own plugin, which at least puts the check-in comments into the source-file.
You just need to install this plugin and activate it in the “Check-In policy”.

Then your source-file will contai the comment, after you checked it in:

/*
 * $log$
 * 
 * Comment: And another test
 *          with a multiline
 *          comment...
 * User: xyz
 * DateTime: 2009-07-23 22:05:24
 * Change: edit
 * 
 * Comment: This is an test
 * User: xyz
 * DateTime: 2009-07-23 21:01:22
 * Change: add, edit
 *
 */

I can also customize (like templates) the position and contents of the comments…

If you are interested in this plugin-in, please let me know…

Just a small addition: Here is a post about “keyword expansion” and TFS; and possible side-effects:
http://blogs.msdn.com/buckh/archive/2007/07/07/keyword-expansion-in-tfs.aspx

EDIT: 2009-08-08:
Today I published my first release of the LogSubstPol on CodePlex.