I use Excel for on-the-fly pricing. We sell to the government and solicitations come across daily that we need to quickly price, based on last selling price. The application downloads sales hitory from the web, analyzes pricing, stores the data in a database, etc, etc. It's really cool and I have a lot of fun just using it (and yes, it is my own creation.)
And, I can tell you this...since implementing this application, sales have gone up. Manually, solicitations can take a good chunk of time to process and calculate, but this app does it in seconds. Oh, and once it does its analysis, it emails the quote to the supplier! How cool is that!