Club Skill has an excellent retrospective on the role of breasts in the history of video games. The article is crammed with illustrative screenshots and amusing factoids; apparently, Dead or Alive Xtreme 2 is the first game to have each breast assigned its own set of physics. Someone's been researching long into the night.

That said, the article is remarkably cleancut and quizzical, with nary a whiff of fanboyish slavering. Especially entertaining is the anecdote about Dead or Alive being named such because it was Tecmo's last ditch effort to save itself, which it did through the power of jiggle physics. And there's more bizarre stuff as well:

When talking about Mortal Kombat and breast physics, this only applies to the recent titles that in the series. This includes Deadly Alliance, Deception, and the upcoming Armageddon. The breast physics in this game seem a bit odd. Probably the best way to describe it is that it moves like very stiff jello. The games even went as far as to add bruising and bleeding. Sometimes matches would end in a pair of bloody breasts.

Boob Physics [Club Skill]