Roleplaying in it's modern incarnation is a hobby that grew from the personalization of figures and reduction in figure scales in wargaming during the nineteen seventies. But it's roots stretch much further back.
Depending on your style, roleplaying can resemble anything from skirmish wargaming to guerilla street theatre. While the roleplayer stereotype of the nerdy, white, teenage, adolescent male does represent a major slice of the market, in fact rolepayer's ages run from six to sixty, and include all races and sexes.
I have been heavily involved in the local Wellington roleplaying community for a number of years, and have helped out at KapCon (Wellington's Annual Roleplaying Convention) for a number of years. KapCon is associated with the Scenario Design Competition which celevbrates the best of roleplaying scenario writing yearly.
Wellington now supports another roleplaying convention, Confusion,
W.A.R.G.S a dedicated roleplaying organization, and a dedicated
discussion board RPG Central.
There is also an LJ community :
wellingtonrpg
The first science fiction roleplaying game, despite the demise of the company that originally published it, it's still going strong. This site contains some discussion and resources for this game.
One of the White Wolf Storyteller System stable, it is portrayed as an epic war for reality. This site contains some discussion of the Mage games I have ben involved with.
From one or two people playing a grown-up form of "let's pretend" to 120 people recreating a grand convocation of wizards from the thirteenth century,live action roleplaying runs the gamut of styles and seriousness.
This site contains discussion, in-character stories, etc., about some of the the LARPS I have been involved with.