Throwing themselves headlong into the community world, Microsoft have introduced the new ASP.NET Wiki

For those not familiar with the term Wiki; A Wiki is a site which has user-editable content right on the page.  Some work on an approval whereby the content is submitted to an administrator, who then approves or rejects the content.  some of the older ones i used to frequent were wide open but they soon got spammed to death so the freely-editable-content flavour are certainly on the decline.  some of the more famous Wiki sits include WikiPedia and openwiki 

So, here's the address of the asp.net one : http://wiki.asp.net/ . Seemed slow to respond for me but it's early days yet.  it's a subdomain of the fantastic and extremely busy asp.net forums so it's good they're keeping it all in the one place