I have an old piece of software (for cutting and plotting vectors onto physical media) (released about 2000-2001) which I use to this day. The software employs a HASP HL with a parallel port hardware lock. I've managed to debug and dump the executable (without the protection). However, when I try it on another of my machines it does not start. The dumped executable will start on the machine that it was dumped on, but not another machine. This would be no problem, except if the hardware key were to break, I wouldn't be able to dump it on a future machine.
Something I should note is that, the software is no longer supported. Since the developer passed away in early 2008 the software has been totally abandoned. Having paid over $2000 for this, without any alternative that I am familiar with, I fear that if the hardware key does break I will be left without software that I use day-to-day.