Kirsten Dunst and Johnny Borrell Photo by: Malibu Media
Caught in the Act!| Cameron Diaz, Kirsten Dunst
Kirsten Dunst, zipping away from Stubb's Bar-B-Q in Austin, Texas, on the back of a Harley-Davidson motorcycle while clinging to the waist of Johnny Borrell, lead singer of British rock band Razorlight. In town for the South by Southwest music festival, the Spider-Man 3 actress scoped out shows and stopped by the Blender House Austin to dance and listen to Albert Hammond Jr. (of the Strokes) perform. Also making the SXSW scene: That '70s Show's Danny Masterson, playing foosball and listening to buzz band Tokyo Police Club, and Cisco Adler and Joe Simpson taking in concerts.

Reese Witherspoon, browsing at Fred Segal Flair in Santa Monica. The store stayed open after-hours so she and her pal could finish up their shopping spree in privacy.

Travis Barker, throwing a 32nd birthday party for wife Shanna Moakler at Cameo Nightclub in Miami. "They looked loving and happy" and acted "really affectionate with each other all night long," a partygoer tells us of the twosome, who say they've reunited since being on the brink of divorce. More than 100 people attended the fete, including Kimberly Stewart, who watched Moakler blow out the candles on her cake as Barker sang an off-key rendition of "Happy Birthday." Then, the birthday girl planted a passionate kiss on Barker's lips while the crowd applauded. "It was very cute," says the onlooker.

Mary-Kate and Ashley Olsen, checking out black tops at Barneys New York in Beverly Hills and zeroing in on a black belted cardigan by Lutz & Patmos. "Both twins took turns trying it on," says a fellow shopper. Later, Mary-Kate hit up Los Angeles lounge Hyde with a group of female friends, who spent the evening chatting. At one point, Mary-Kate and a pal headed outside to share a cigarette and talk on their cell phones. "They were having a really fun night," a clubgoer says.

Canter's Deli Photo by: Ben / Bauer-Griffin
Caught in the Act!| Cameron Diaz
Adam Brody, having a guy's night out at Hyde, followed by 3 a.m. noshing at L.A. staple Canter's Deli. The former O.C. star and eight friends ate a late dinner (or early breakfast?) of french fries and black-and-white cookies with milk. "They were all just coming and going, relaxing, being real casual, stuffing their mouths, standing up (and) sitting down and managing to eat all at the same time," a customer tells us, adding, "Great times."

• By KELLY LUMPKINS, JENNIFER GARCIA and STEVE HELLING