These guys created a business letting people Buy Bacon online and bacon realted stuff. Some very cool insights. And great tips for prefab'd services that make it much easier to run a web/mail-based business.
Here's a short list: Crazyegg.com for landing page analysis, Endicia.com for a great way to deal with postage (interface to the USPS' scary API, has an awesome Mac client--seems like Opentaps does a similar thing), Uservoice for onsite feedback.
Business model: Selling t-shirts for a high profit and lots & lots of the world's best bacon for a lesser profit per item. And being smart as hell about every aspect of marketing & operations, totally leveraging new technology like the above.
Brilliant and fun presentation. Built the biz in 3 weeks. Paid tshirt models in PBR & Pizza. Presentation soon in SF.