I’m off to PyCon 2007 (Dallas, TX) in the morning. I managaged to get into the Advanced Django tutorial (which I’m really looking forward to), so I’m heading up a day early. If you happen to be there, hopefully we’ll cross paths!
A Short History of Nearly Everything by Bill Bryson -- a true tale of scientific thinking throughout history. You'll be amazed by how much we still don't know.
Getting Things Done: The Art of Stress-Free Productivity by David Allen. I'm a bit of a GTD freak since reading this, but productivity == $$ (whether you can simply get more work done in a given time, or work less by focusing on the right tasks.)