Tis also on TED
The maths equations are an excellent idea.
www.ted.com/talks/david_merrill_demos_siftables_the_smart_blocks.html
EDIT
Ahh yes was from TED, it pays to play the first 3 seconds of the video before commenting on it :S
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redazril I LIKE DRUGS!, Fri 27 Feb 2009, 14:49,
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