With or without little kids by their sides, many celebrities celebrated Halloween on Wednesday. Sandra Bullock went with a "Toy Story" theme, dressing up as cowgirl Jessie in a red cowboy hat and cow-patterned pants. Her son Louis wore a Buzz Lightyear costume.

Singer Chris Brown, never one to shy away from controversy, dressed as a member of the Islamic fundamentalist terrorist group the Taliban to attend a party hosted by Rihanna at Greystone night club in Hollywood.

Avril Lavigne wore a sexy sailor costume to dinner with friends at BOA Steakhouse in Beverly Hills.  Earlier this week she was left red faced after her ex-husband Deryck Whibley mocked her in an costume made to look like the pop star.

"How I Met Your Mother" star Alyson Hannigan is a huge fan of the holiday and each year steps out in a fancy costume with her family. This time she, her husband Alexis Denisof, and their daughters Satyana and Keeva wore matching seahorse outfits.

See more celebrities in Halloween costumes...