BuzzerQuiz
The fast fun quiz game - open and student quiz competitions in the UK, including the Championship Series and the British Student Quiz Championships. Matches closely resemble University Challenge / College Bowl.
http://www.buzzerquiz.com

Mind Sports Olympiad
Organisation based in London that provides an event for lovers of games and mind sports to battle for prizes.
http://www.msoworld.com

Quizzing.co.uk
UK quiz portal featuring advice on getting on TV quiz shows and contestant calls. Also includes user tools, forum, events and services.
http://www.quizzing.co.uk