Quick Reference Reference

Just stumbled across this page of links to "quick reference" cards and pages:

http://www.digilife.be/quickreferences/quickrefs.htm

I think it would be a cool thing to have a web application which lets you build a customizable quick reference guide. From a grand master template, you would pick tools for which you wanted quick reference guides, and then within the guide itself you would pick which features you wanted included on the guide, so you only include reminders for what you tend to forget.