mathematics 

klarner project combinatorial games coin changing three cubes brick packing googlelinks 
I'm an amateur mathematician.
I'm mostly interested in recreational mathematics and combinatorial
games. I like algebra, number theory, and cryptography too.
Once I was President and CEO of a little publickey cryptography company [website archive] that was (eventually) acquired by VeriSign, but there wasn't much in the way of "real" mathematics involved in that—it was software development instead. You can drill down on some subtopics using the links at the left. Here's a trophy I've kept from graduate school. 