A TF2 board game would count if it has a modest amount of original gameplay and isn't a total reskin of a pre-existing board game. Some appearance in someone else's game like being playable in that Sonic Racing Transformed doesn't count, but a digital pinball table for Pinball FX like Portal got counts. An appearance in a non-Tf2 game could count if in theory it could be considered a game into itself. Like a substantial enough minigame in a minigame compilation.

And it has to be more interesting than that TF2 Peggle thing.

I think I heard something about some of the voice actors returning to Valve for an unannounced project.