Once again, Joel is a great resource.

In this article he links to the project specs for Aardvark which is a remote help system that you can use to help your aunt get her pc working again (if she can connect to the internet).  The product itself looks nice but I'm more interested in the spec itself at this point because of the best practice gems it contains.

Example 1:  Use CSS for formatting but tables for layout because CSS layout support is so buggy in modern browsers.  This is especially true if you have to support multiple browsers.  Trying to lay this out with div's can be an extreme exercise in patience. 

There are other examples such as making the user experience as simple and easy as possible.  Don't make the user answer unnecessary questions that they don't know the answer to anyway. 

It's worth a read, especially if your looking for modern web best practices as many sites out there are still publlishing information from 1999-2000.