A Lego maker has built a Lego walker based only on pneumatics. This build contains no electronics or programmable bricks at all. Granted, there is likely a non-Lego air compressor for the build.
This Walker is an great bit of work, and considering my last attempt with Lego pneumatics was a simple 3 cylinder reciprocating engine, I am definitely impressed. This machine must have taken plenty of time and quite a few attempts to get right!