In order to reclaim some of our programming mojo that has waned from years of maintenance programming and meetings, a couple of us programmers decided to go and try to learn a completely new language--Haskell.
I think this expedition was spurred by a blog post titled Great resources to learn Haskell. I'm as much a math geek as I am a computer geek--I competed on my high school Math Team--so a functional programming language is a natural fit for my hobbyist interest.
Resources that I've used so far:
Haskell for C Programmers is a online book that resonates well with me, because of my deep roots in C programming.