I have always been obsessed with maps. Maps and statistics. If I could only take one book to a desert island with me it would be an atlas. No shit.
At the end of last year I stumbled upon an app called Endomondo. This free little bit of software uses GPS on your smartphone to track your bike rides. Over the past year it has developed to also offer the user all sorts of amazing bits of information about almost a dozen different things.
I love getting home from a ride and sitting at my computer and nerding out on the various stats I've collected. It's become obsessive, and no there is talk of soon spending hundreds on a GPS cycle computer (with heart rate monitors and cadence monitors too).
Sometimes though I'll go riding for riding's sake. No measuring. No destination. No nothing.