I don't actually end up RP'ing much, between my own time constraints and the difficulty of actually getting an RP rolling, let alone keeping one alive.  So great characters and stories are few and far between for me.  To look at it optimistically, though, these restrictions make the brightest times shine even brighter.  I remember vividly the first time I came to this site and how bad I was at making interesting characters (disclaimer: Spoo is still bad at making interesting characters).  The first RP that got off the ground for me was a Highschool of the Dead spinoff.  Daichi, my character, was a dork (unintentionally; I was shooting for "reliable, tactical thinky type" and wound up with anime Dwight Schrute) and at one point I accidentally initiated sexytime because he was sleeping shirtless or something.  Bad writing on my part, but it still turned out to be a fun time.

There was one RP I was in that was based off Baka to Test.  Comedy, school life, slice of life -- that sort of thing.  My character was Itsuki Akoto.  Another thinky type, but this time a charismatic dude and closet supervillian who manipulates people to get his way with no regard to their feelings.  Still my personal favorite character of my own creation to date -- we had a weekly poll on that RP voting on favorite characters and happenings and such and Itsuki won once.  Not exactly a Pulitzer, but it made me happy to know someone enjoyed his scenes regardless.