If you, like me, is a programming language fetishist, then you'll love Wouter van Oortsmerssen. I first became aware of him when Amiga E was rapidly gaining popularity with the Amiga crowd.
Wouter is one of those rare guys that never seems to run out of interesting concepts for new programming languages, as can be seen on Wouter's programming language page. Languages include Amiga E and the seminal False, as well as more bizarre languages like G, Apfelstrudel, Kartoffel and Sauerkraut (the latter three visual languages).
His programming language page is well worth a read...