I'm a problem solver. There is nothing I enjoy more than taking an interesting problem and analyzing, deciphering, decomposing, re-composing, and just generally tinkering until all the pieces elegantly fall into place.
This also tends to mean that I'm an autodidact. If I don't understand it, I'll study it until I do.
I also really like the JVM; no like seriously... This means I use Java (obviously), GWT, and Clojure to get things done.