Are there any wiki websites where people can post biographies of a common person?

I think that family and friends of the deceased would be interested in writing their own biography and read others’ biography too. Does this already exist? I’ll bet it could become quite popular. Has anyone seen similar websites or websites which can basically do the same thing?

How common is “common”? That is, at one point does a person stop being “common” and start meriting mention in Wikipedia, for example?

Common = anyone who wants to and has access to the internet.
Say my Grandfather dies. I want to, in the mourning period, have private dicussion with family and friends as we mourn together. (I know this could be done on facebook, etc…) After a certain period of time I think that me, and my family and friends might want to write some history on my Grandfather (can this be done on Ancestry.com?). As I understand, wikis would make a great style of website for this undertaking. I’m asking if there is a website dedicated for these purposes?

Wikia.com might let you host a personal site, as long as there is a theme to it.

There are lots of wiki software so you can host your own rather cheaply with GoDaddy and other sites and just upload the wiki software to your account

Some newspaper websites post obituaries for any recent deaths (not just notable ones) and allow visitors to the site to post comments on a “guest book” presumably to be read by the family. There is a commercial company called Legacy.com that operates these memorials for many papers in the US.