I like the company wiki, but which ones are currently 'hot'?
Do you use a:
* self hosted product (mediawiki, tikiwiki, docuwiki),
* as a service (wikihost.com),
* part of a larger product (atlassian, trac, redmine)
* part of a larger service (github), or
* something else maybe?
If you can also explain something noteworthy (good/bad) about your wiki that'd be nice as well..
