For my current CS:S map I was originally going to create parody advertisements for billboards, posters etc but have decided to advertise MODs instead. I'm currently in the process of contacting mods and asking for their approval to advertise them in game.
If you're a team member of a mod and would like some in game advertising reply to this thread. If you can provide concept images or other cool art that could easily be made into posters, billboards and shit that would be great too.
Doesn't matter what engine the mod is for, as long as it doesn't suck balls.
This is the discussion thread for the map itself