Even if you don't have a fondness for building-sized, stomping war machines, you might find this detailed interview and pictorial about the process of designing, from concept to texturing, a mech interesting.
Do you like musical instruments with lots of keyboards? And lots and lots of dials? Then you may like 36 15 MOOG: Stuff with Moog and/or 60's and 70's vintage synths in it. (related Ask MeFi) [more inside]
I'll tell you one thing: if I was in London, I'd mosey on over to the Kinetica Art Fair. It looks like fun.
David Byrne writes three thoughtful essays on robots, song, and the uncanny valley on the occasion of the creation of a robot which sings in his voice at a Madrid museum: Visiting the robot factory in Texas, regarding the uncanny valley, on machines and souls.
Cockroach Controlled Mobile Robots — Overview: an experimental mechanism that uses a living Madagascan hissing cockroach atop a modified trackball to control a three-wheeled robot. If the cockroach moves left, the robot moves left. Infrared sensors also provide navigation feedback to the cockroach, striving to create a pseudo-intelligent system with the cockroach as the CPU. Garnet Hertz, creator of Fly with Implanted Webserver and Cockroach with Wireless Video, has used Gromphadorhina portentosa on three generations of autonomous roachbots (YouTube video and Ars Electronica 2005 gallery).