Ashton Kutcher: Janet Gough/Celebrityphoto.com

Ashton Kutcher

Age 25

Not since Jim Carrey has playing dumb paid off so powerfully: The star of ''That '70s Show'' (for which he'll be paid $6 million-plus for two more seasons) is an investor in L.A.'s trendiest eatery (Dolce); Demi Moore's enviable boy toy; and, as creator and host of MTV's breakout hit ''Punk'd,'' king of Hollywood's Junior Glitterati. His big-screen credibility should get a boost from Cameron Crowe in next fall's romantic comedy ''Elizabethtown.'' Kutcher couldn't save ''My Boss's Daughter'' -- but then probably not even Carrey could have done that.