At which sites can you get a profile nowadays?

I’ve whipped up a quick website to aggregate all my profile information from the different websites I have a profile at, but I can only come up with very few, even though I’ve made accounts at most any site I come across. Which popular or less popular sites am I forgetting?

Sites I’ve thought of up till now: Last.fm, ICheckMovies, Goodreads, 23hq, Google Reader, Twitter. Note that I only use one site per type of service, e.g. I explicitly did not include Flickr because 23hq I use 23hq for photo sharing.