HL2 is simply ace, the gravity gun is the best, and if you play in deathmatches, as i do with my kids,you certainly learn how to use it to great effect.
I think the gravity gun has its place, certainly if in deathmatch, its upto the admin to set weapon's so it aint a problem there. But that final level were you only have a gravity gun is a joke. point fire, instant death to bad guy, spit out, kill more bad guys. This was impressive at first, but dull after the second time.
It is the closest thing I've ever seen to a Doomsday Device (see
http://www.planetquake.com/expert/GameDesign.html ) in any game, not to mention very boring (I enjoyed the level with the priest, but I felt I had fully explored the gravity gun by the end of it).
Other doomsday devices so far have been limited severely, even if only by lack of ammo.
