I finally got round to trying my hand at microcontroller programming. Following this instructable it was dead easy.
The main problem I ran up against was in the software. On Linux you need the ppdev module in order to have access to /dev/parports. In menuconfig it's Device drivers -> Character devices -> Support for user-space parallel port device drivers.
On Debian you need the following packages:
avr-libc binutils-avr gcc-avr avrdude
Your user also needs to be in the lp group for access to the parallel port.