If you’re using a non-Leopard version of Mac OS X you still have a less-expensive option. If you go to LogMeIn.com you should be able to download a free version of the program for either Windows or Mac (there’s a paid version available too so make sure you don’t download that one by mistake…you don’t need it). Once you’ve installed LogMeIn on both your machine and your parents’ machine, you should be able to connect to their machine using nothing more than a password for their machine and a web browser…and since it’s all within a web browser, you can even do so cross-platformn (ie Windows can log into a Mac, and vice versa).

Sean’s note: If you both have the newest version of OS X, better known as Leopard, there’s a new feature in it that allows you to share your screen with a remote user. Go to the System Preferences menu under the Apple menu, click on Sharing, and then enable Screen Sharing. An IP address will be listed in the right-hand pane that can be used to get to that computer; the only downside here is that it may be a local (ie behind your router) address that’s not accessible from the internet. One way you can get around this is by signing up for a .Mac account, and making sure both computers are using the same .Mac account, then enabling “Back to My Mac” in the .Mac control panel…then your parents’ computer should appear in your finder, and you can right-click it and choose the screen-sharing option. This option should work just fine even if you both have firewalls, because the .Mac server keeps track of where both of you are and makes the connection for you.