Somebody just asked me where they could find 'more things like this'. It's a good question, and it's harder than it should be. Here's what I know about:
The London Sandpit runs every month, more or less. http://sandpit.hideandseekfest.co.uk/events/. There's a bigger version, called Hide & Seek, once a year. Free.
Iglab does the same thing, in Bristol. http://iglab.urbanantics.net/www/. The bigger version's called Igfest. Free.
The Fun Fed run game sessions every week or so. http://www.thefunfed.com/. They're £10/session, but often the first one is free.
Tin Horse Theatre are up to something. http://www.tinhorsetheatre.co.uk/
That's all I know, in terms of active real-world games within striking distance of London. It's taken me a long time to get that far - I'd love any suggestions.
There aren't vast undiscovered swathes that you just happen not to have stumbled across, really.
<a href="http://barg.org.uk/">BARG</a> is in Birmingham.
<a href="http://youhavefoundconey.net/">Coney</a> does things mysteriously but pretty frequently.
<a href="http://www.gluehq.co.uk/scratch.html">Scratch Interact</a> is interactive theatre - not games, but some kinda playful stuff. <a href="http://www.gideonreeling.co.uk/">Gideon Reeling</a> does occasional games though the website isn't very informative. Places like BAC and Soho Theatre have gamey things every now and again and are worth keeping an eye on. One of the London universities has a few people who are planning on starting a pervasive games group.
We always try to write about one-offs on the <a href="http://sandpit.hideandseekfest.co.uk/blog/">Sandpit blog</a>, but are sometimes too lazy or busy.
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