I was playing Half-Life 2 Team Deathmatch a couple of nights ago, mainly to justify my monthly broadband expenses and keep my eye in, because I've not played against real people for a couple of months. I'm doing pretty well, in the top 4 of a 16 player server, which is about as high as I aspire to, and suddenly in the middle of a game on the Warehouse map, I see the coolest in-game exploit I've ever encountered online.
Half-Life 2 Deathmatch is unique due to the fabulous gravity gun, which you can use to pick up trash and either block bullets with it (should the object be robust enough, and not be, say, an explosive toxic barrel...) or fling it at other people to bludgeon them to death. Now, the warehouse map is basically a ruined three storey structure set in the middle of a plaza, with narrow streets arounding all four edges of the building. It's a tight map, with not much room to manoeuvre. The rocket launcher, possibly the most potent weapon in the game, is on the top floor of the warehouse, and it's hard to get up to the top floor through the building if people are already camping inside. A couple of clever players have found a way of getting to the top floor without entering the building. Obviously, they can't rocket jump, because they don't have a rocket launcher yet. No, instead they use the gravity gun in an absolutely astounding way.
Firstly, they jump up onto a fairly large object, say a filing cabinet, look down at it, and jump. When they're in the air, they use the secondary fire of the gravity gun to drag the cabinet up to them. Then, in the fraction of a second that they have when the cabinet is beneath their feet, they jump up again. By repeating this process quickly enough, they're able to magic carpet ride and levitate into the air, whisking themselves up to the top of the building in a couple of seconds, (effectively bypassing half the level) where they can then grab the rocket launcher and lay the smacketh down. It must really be a hard trick to execute, because I only saw it get used once or twice, and it also leaves you completely vulnerable if you get caught mid-levitation.
Fantastic little exploit, though. I'll have to see if I can master it.