(using MapTool and a chat client)
Having my players discover the phrase 'Beware of Travis' carved into a wall.
Having one immediately yell about Taxi Driver and post a link to a picture of the character looking crazy with his guns.
Immediately grabbing the picture, cropping it down, and dragging it onto the map as the bad guy emerged from the secret door behind them...
Less good - MapTool crashed at one point and ate the entire campaign, so all the mapfiles and fog-reveals had to be rebuilt. Never had that happen before.
Also, one player is trying to convince me to rewrite all these 1st edition pre-advanced D&D modules into 4e. ARGH. I'm not doing it, but I have allowed some 'minor' (huge compared to what OD&D should be, minor compared to porting to 4e) rule changes designed to make the game an awful lot easier and more likely to achieve my goals.
See, I hate combat. I'm an explorer both as a player and a GM. What I really want is for my players to wander around the module, see everything, trip all the traps, go "ONOES", pick themselves back up again, and keep going. Killing them off is not fun. Life being slow and dangerous enough that the party proceeds at a crawl and wants to be fully rested all the time is dull. If letting the wizard cast Magic Missile once per combat instead of per day means the party will keep moving, then I'm okay with that.
Said player still thinks it would be more fun if we used 4e so the fights would be more interesting. BUT I HATE COMBAT! Fights are boring? Good, stop having them! :)