I Love Threadless!
www.threadless.com that is. If you haven't seen it, go check it out. It fits the model of long term staying power in web 2.0 land. And what is that model?
Immersive - You can get lost on threadless for hours looking at and commenting on all the designs, blogs, photos, etc.
Expressive - Threadless allows members of it's devoted community to express themselves in all sorts of ways. Designers can upload their designs, have them voted on, commented on and produced (if enough people vote for them). Consumers can grade designs, comment or suggest improvements, create blogs, or even get into the act themselves by submitting slogans for "Type Tees". You can also get credit for uploading photos of yourself in threadless shirts.
Transparent - working with or purchasing on threadless is a seamless process that is hassle free.
When online businesses come into existence that bring immersive, expressive and transparent experiences to consumers, success is sure to follow.