By Anne-Marie Otey
March 09, 1998 12:00 PM

Several months ago, we spotted Jim Carrey in the Hotel Bel-Air, singing his heart out at the piano bar. Now the $20-million-per-movie man is at it again. Last month, Carrey, an honoree at the AIDS Project Los Angeles Commitment to Life benefit at the Universal Amphitheatre, shared a dressing room with award presenters Merv Griffin and Dustin Hoffman plus a baby grand piano. “This guy’s got some chops,” Hoffman told Griffin, pointing to Carrey, who wandered over to the piano. When Griffin started playing “When Sunny Gets Blue,” Carrey belted out the ’50s standard. “Merv was amazed that Jim knew the lyrics,” my source reports. “He hit every high note.” When Carrey was called away to go onstage, Griffin told him, “You have a standing engagement anytime at the Coconut Club,” his new supper club in the Beverly Hilton Hotel….

The latest party game in Hollywood may be “How to kill off Melrose Place cast members.” Scriptwriters face a challenge as they prepare to unload five regulars next season, most notably Andrew Shue, who plays doofy ad exec Billy Campbell. He’ll take his TV wife, Brooke Langton, along with him, plus relative newcomers Linden Ashby, Alyssa Milano and Lisa Rinna. The sole surviving original cast member, Thomas Calabro, will return, as will Heather Locklear, Jack Wagner, Rob Estes, Kelly Rutherford and Jamie Luner. The show ends its sixth season with a two-hour cliffhanger March 30. “As storylines run their course,” says Melrose bigwig Aaron Spelling, “we will say goodbye to a number of characters.”…

Singer-songwriter Fiona Apple, 20, broke up with Gen-X magician David Blaine late last year and moved quickly into a new romance with another wunderkind: Paul Thomas Anderson, the 27-year-old writer and director of Boogie Nights. I hear that the couple are living together—at least when both of them are in L.A….

In 1993, Jewel cowrote one of her hit songs, “You Were Meant for Me,” on a weekend trip to Mexico with then-boyfriend Steve Poltz, who later appeared in the pop vixen’s video for the tune filmed after they had split up. Now I hear that Jewel sings harmony on three love songs for Poltz’s debut solo album, One Left Shoe, due March 17. So has the couple reunited? “No,” says pop-folkie Poltz. “People ask me if we are going out all the time. We’re not. It has evolved into something better. We have a great friendship.”…

It wasn’t exactly business as usual for Katie Couric’s return to the Today show Feb. 24 following the death of her husband, attorney Jay Monahan, from colon cancer in January. Cohost Matt Lauer opened the show and squeezed Couric’s hand as she thanked the people “who’ve made contributions to the National Cancer Institute in Jay’s memory” and the writers of many “heartfelt letters.” Then Couric went on with the show, interviewing Monica Lewinsky’s attorney William Ginsburg, among others. “There wasn’t any kind of drama [on the set],” says a source close to Couric, who now wears Monahan’s wedding band around her neck. “She’s doing OK. She’s very happy to be back and has unbelievable support from everyone on Today. We’re here to help her through this in any way we can.”