I live & work in London UK in software development and open data.
I helped kick start the monthly meet-ups in London in 2008: en:Wikipedia:Meetup/London. Still try to get along to them, but missed a few lately.
I'm a big enthusiast and heavily involved volunteer for en:OpenStreetMap the worldwide open data map making collaboration modelled on wikipedia.
I am great believer in the wiki processes which have made wikipedia possible, and which continue to help it grow bigger and better. I believe that wikimedia is a force for good, in a web dominated by boring old capitalism.
Involvement in various WikiMedia projects:Edit
Wikipedia en - en:User:Harry_Wood - I wouldn't say I'm a big contributor to wikipedia itself. I just try to chip in here and there when I see something is missing/wrong
MediaWiki.org - mw:User:Harry_Wood - Mediawiki is a great bit of software. I was quite active on mediawiki.org for a while helping to document it. In particular I wrote a lot of the public domain help pages.
WikiBooks - wikibooks:User:Harry_Wood - I love the idea of wikibooks. Not all information is encyclopaedic, so let's make other types of books! But I'm not sure if the process of writing a book, of composing the narrative, is suited to wiki style collaboration. I shall chip in to try to help it work though!