Katy Perry may have "won" Halloween for "most original" costume, when she dressed up as a giant Flaming Hot Cheeto and used an actual Cheeto bag for a purse. She arguably stole the show at Kate Hudson's annual Halloween party. Kate Hudson and her mother, Goldie Hawn, dressed as bikers from the popular show, 'Sons of Anarchy'.

Although the party's stated theme was bikers, Gwen Stefani and Gavin Rossdale dressed as vampires. Nicole Richie dressed as the Disney villain Cruella deVille. Jessica Alba did a cross-dressing number by going as the Guns N'Roses singer Slash.

On a side note, Matthew Morrison threw his annual costume party at Hyde in L.A., which typically draws a younger crowd. One of the stand-outs there was Lucy Hale, who dressed up as the Twitter bird in a feathered blue costume with white angel wings. Morrison himself and his wife, Renee Puente, was dressed as characters from 'Pulp Fiction'.

The Casamigos Tequilas party is another annual Halloween party. George Clooney, Rande Gerber, and Mike Meldman are the co-owners of the alcohol brand. However, Clooney was overseas, leaving Rande to play host along with his wife Cindy Crawford. They dressed as singers Gregg Allman and Cher respectively.

Paris Hilton was there as a very humanoid Minnie Mouse, and Tim Allen and his wife, Jane Hajduk, dressed in Western gear.

Other celebs who dressed up for Halloween included Kelly Osbourne as Magenta from 'The Rocky Horror Picture Show' and Robin Roberts who cross-dressed as the tannest version of Elsa ever. GMA host Amy Robach dressed as Maleficent (It seems there was an unofficial Disney theme this year).