Things #1, 3, and 4: User-Driven Websites

User-Driven content of websites have increased the value of those websites exponentially. Sites like Library Thing or Ravelry are excellent examples of this. Ravelry is a knitting/crocheting related website where the user can catalog their projects, yarn, needles, books, favorite designers, ideas, etc., as well as numerous forums. If it weren't for the user adding the design, yarn, pattern, book or what-have-you, there would be a dearth of content. Wikis also utilize this feature. The applications across the internet are endless, so jump in and have your say!