It's fun to look for design trends you're accustomed to seeing on the web in everyday products. You've seen circles for profile pictures in Google+ Circles.

The new Basecamp also uses them, as well as OS X Lion's login screen.

They're also used on boxes of Lipton tea.

I'm sure the iOS linen background that originated as the background behind pages in mobile Safari will one day feel like Aqua buttons, but I like them, and variants of the pattern are probably all over your house.