Remotely connecting to your parents' computer to show them how to send email or file their taxes is fine if everything's working correctly, but how about when there's some sort of hardware or operating system error? IOGear's PCPortal actually bypasses the issue entirely by being a hardware solution that hooks directly up to an Ethernet port and to the computer you're trying to connect to like a KVM.
This way, you can control the machine from the comfort of your own home, diagnosing problems that you couldn't otherwise manage (if Windows doesn't boot up all the way, for example). It's also quite efficient for fixing machines that do boot up, but have various software glitches that prevent you from remotely tunneling in. The PCPortal costs US$499, but if you're frequently administrating other people's machines, or if you need an easy way to get into your own from the outside world, it's a decent investment. [Iogear]