I've got two. A silver one that's about 3 years old, and a blue one that I bought at a Performance sale because I started to worry that the silver one might be getting old. Now that I own two bikes, it's nice to have a spare helmet (I rotated the silver into spare status), in case someone wants to ride with me. My 6'3" brother visited this summer, and we cranked the stem up as high as she'd go on the Larkspur, he popped the helmet on his head, and off we went.
I like helmets that have a little adjustment wheel in the back to make them looser or tighter. When I do a triathlon, I put my hair in a french braid, and need a bit more room in the helmet. My brother needed a lot more room--he has a big noggin!
I never thought of coordinating my helmet color with anything until I came to TE! Now I want a Celeste helmet to match my beauteous Bianchi.