These days, Marilyn Manson has to take unusual measures to shock people -- like singing Justin Timberlake's 'Cry Me a River' six times at a bar during a night of partying.

The one-time 'Antichrist Superstar,' now 42, spent the weekend in Las Vegas, where, according to the New York Post, he attended a Halloween bash at The Bank nightclub and downed "numerous shots of absinthe."

When Manson and girlfriend Lindsay Usich were unable to find a karaoke establishment open at 4 AM, they headed to a bar called Born and Raised. There, according to a source, "More shots followed, some shotgunned beers, before Marilyn got on the mike and sang the Doors’ ‘Texas Radio’ and a pretty-good version of Timberlake’s ‘Cry Me a River,’ which he sang six times."

Apparently, Manson was so insistent on performing the JT song that someone had to download it on an iPod for him. Manson later became angry at the venue's poor sound system and got into a fight with a limo driver, but before going home for the night he explained himself: "I am sorry I went nuts, but I’m a rock star!"

While Manson's love of Timberlake's R&B music may seem strange, the rocker has always had a soft spot for the former 'N Sync-er. Back in 2007, the 'Beautiful People' hitmaker sang an acoustic cover of 'What Goes Around... Comes Around' for BBC Radio 1.