Iron Man 2 was a big disappointment in a lot of ways. It lost quite a bit of its energy from the first entry. Whiplash (Or Whiplash + Crimson Dynamo) was the start of Marvel's long list of incredibly disappointing villains. Tony Stark also was much whinier and less awesome than
the tank fighting version of the original.
One of the best parts of the sequel though, was Tony Stark's weapon-making competition, Justin Hammer. Played by future Oscar winner Sam Rockwell, he had several running jokes throughout the film that almost made it worth it. The best of these was the ex-wife joke. When showing Rhodey all of the weapons he wanted to outfit War Machine with, he shows off his favorite piece. The cigar-shaped missile was supposedly his masterpiece. When Rhodey went to use the ex-wife in the final battle though, it was a complete dud. By far the worst weapon in the entire extended franchise.