I've been busy this week, and have just released new versions of Algorithm::FastPermute (more portable) and PadWalker (less buggy). Peter Scott has written a patch to the Perl debugger which uses PadWalker to allow you to inspect lexical variables from the debugger. I hope that it will actually work now, and get into 5.8 before it's too late.
Otherwise, I'm mainly learning category theory. I keep trying to read papers in computer science which don't make any sense at all because I don't grok the categorical language. Also, I want to learn categorical logic (toposes and so on); and there's no hope of that until I'm fluent with the basics. The most interesting thing I've learnt so far is that "A comathematician is a system for turning theorems into coffee".