here's an IDEA/way someone did it. and here
Another way you may wish to install or use a USB drive would be to add a PCMCIA USB car, usually quite cheap on ebay, like $15-30.
Or like some suggest, pull the HD and hook to another system and copy the needed files or install the OS on another computer using the laptop drive as the main drive, achieved by using a 2.5 to 3.5 adapter, available at many locations.
-Mike