M.C. Escher is surely the most popular artist among mathematicians and scientists. His explorations of symmetry and tricks of perspective and perception and his playful use of geometry all explore themes that are important across all of these fields. Several LEGO builders have taken on Escher themes. The first prominent effort was by Andrew Lipson and Daniel Shiu, who recreated five different Escher works in the early 2000's. In 2005, Henry Lim was commissioned by the Hong Kong Science Museum to make his own takes on four Escher pictures. Others have explored this work in LEGO form as well.
Perhaps the most popular Escher work in LEGO form is Relativity. Here is a version by Andrew Lipson and Daniel Shiu.
And another by Henry Lim.
Paul Vermeesh just recently posted a Star Wars version (which is what prompted this post).
Profound Whatever did a space version.
NewRight did a castle version.
Here's a version by Supernerd23
Big Daddy Nelson built this vignette
Thanks to Nannan of the Brothers-Brick for tracking down a couple of those links.