Using Parallel port to Power circuits
The PC parallel port is not designed to power external equipment.
 While it xcan be used for his the power levels obtainable are low.  

Better, if available, is USB.   

Even a serial port MAY have greater power capability. 



Parallel port pinouts are given here  and here and here and here

I provide several pages as, when you are trying to do something non standard, seeing what various people say can help.

Below is  a typical pinout table.

Any one of the output pins may supply some current.
 If you take all outputs, connect a 1N4148 diode from each facing "outwards" (Anode to port, cathode to output) , connect all Cathodes and add a capacitor o ground (say 10 uF) you will get some voltage. How much and at what level is to be determined.





This page  reports that Linksys, who should know better [tm] have drawn power from some pins for some of their equipmenty. eg


"Another area that might be of interest in your document would be some
comment on the parallel port extenders. I have a xmit/rcv pair from LinkSys
that I bought from Fry's Electronics for about $70. They convert the parallel
signal to a serial data stream, using the signal and control lines for power.
My set was working fine until I added a hardware dongle for an expensive
Windows application. Then, printing ceased to work reliably. I took the
transmitter apart and partially traced the schematic.   

They have used 7
diodes to suck power from pins 13, 14, 15, 17, 1, 2, and 3.    

Also, they
connected pins 15 (ERR) to 16 (INIT). The strobe line is coupled in to a
flip-flop, which starts clocking the parallel loaded data."