[jester710]

Some options:

-If you come at the first of the year, there's the Rose Bowl and all the accompanying hoopla.
-San Diego Zoo/Seaworld.
-Mann's Chinese Theater/Hollywood in general.
-Several casinos in the area, including Bicycle Club and Commerce.
-Many restaurants/nightclubs that are good for seeing stars, if that's your thing.
-Lots of beaches (although "warm" in January will be high 50s/low 60s, and you do run the risk of rain).
-Lakers or Clippers games; Clippers are cheaper and less packed, while the Lakers have the Hollywood crowd. Or UCLA/USC basketball, if you prefer college hoops.

That's all I can think of off the top of my head.