Have been building a bit of lego with the kids (perhaps to use the figures in a D&D game even). This seems like a good excuse to post some images by people out there who have recreated Escher's wonderful imagery in lego no less.
Andrew Lipson's work is very clever, starting with Relativity, then Ascending and Descending and the more cheaty Waterfall:
[images sets of escher/lego constructions from Andrew Lipson's site]
Check out his neato homepage image as well - very clever.
Since we are on the topic of lego - we should visit the Brickartist himself Nathan Sawaya. The work is clever and brings a level of thought as well as artistry to the medium. Much like computer work which might have to built things with limited pallets or low resolutions - the lego work is all the more intersting because of the limitations.
[images of 3 pieces od Nathan Sawaya lego art from his website]