TF2 vmfsI've finally started to open and check out the TF2 .vmfs which are included with the Source SDK, and i must say they are very informative and interesting.
Besides instantly being able to see what the TF2-specific entities are and how they work, you also get a peak into how valve optimizes their maps and some cool tricks they use.
If you would like to check out some .vmfs that are not included with the SDK, try
here.
I would highly recommend any source mapper to check these out, whether or not you map for tf2.