Those of you that have longterm, genuine online friendships- how did you meet?

Nothing romantic, just simply platonic friendships. It's always been mind boggling to me when online friendships seem to stick for folks, because most've the connections I've made online have typically fizzled away.

Where did you meet your friend/s? What kept you coming back to chat, hang out, and get to know each other? Have you met in person or have you planned to?