I must admit to being slightly interested in famous people with the last name Christensen. Christiansons can go jump off a bridge for all I care, but Christensens, now those are interesting people. So I went on a miniature little quest to try and find a movie in which "actor" Hayden Christensen does not suck horribly. And by miniature quest I mean that I watched Jumper on my flight home from Chicago (why is it so much easier to watch horrible movies when they're in-flight, on a horrible 4-inch screen?) and then I got Shattered Glass from the library. Surprisingly, Glass, based on the true story of Stephen Glass, a journalist for The New Republic who turned out to be a big fat liar, was actually a pretty good movie. Not because Christensen did a good acting job, but because he did the same thing he's done in every other movie he's been in, which is act like a big baby. Only that's what he was supposed to do, so it actually turned out OK.
The other Christensen I know of is Erika Christensen, who is interesting in that she is (a) cute, and (b) went from the Oscar-winning Traffic to the teenage stalker flick Swimfan.