I know this is kind of old news in the fashion world, but the Givenchy Fall 2011 collection was crawling with feline femme fatales. I really liked the velvet cat caps that the ladies were all sporting, and though I might not wear it in my every day world, I'd totally consider it for a bike helmet.
A $2000 bike helmet. Meow.
image 1, 2 | image 3 from Glamour, Spain