I don’t keep an “official” list anywhere, but you can find most of the ones that I find interesting over on my del.icio.us feed. Some of the ones that caught my attention recently are:

TechPresident’s wiki that documents the staff working on tech side of presidential campaigns in 2008.

I also really like the “Wikiscanner,” which lists anonymous edits to the Wikipedia and where they came from, e.g., the White House, etc.

Finally, I was talking with a number of the members of Cernio — a technology co-operative based out of the Bay Area — and it turns out that they’re involved in the DavisWiki listed above. And, to my surprise, they also host the newly launched Torontopedia initiative. All great stuff.