Heatseekerz.net have posted Part 3 of their HX08 Mod article, which titled "Driving The Window's Leds". In this part they describe briefly how to drive the leds from a previous article on a window mod. Heres a snip:
Theoretically speaking, it is possible to drive the leds directly from the parallel printer port, just plug the led in the printer port and place a resistor between them. Practically, the leds I used, need way to much current to work properly. Applying these leds directly on the printer port would cause irreparable damage to your system.