Landing Page Product (LAPP)

I want to build, and encourage others to build, this kind of web product:

• You get immediate value from the product, right from the landing page.
• No signup needed to use (initially).
• No purchase needed to use (initially).

The idea started with this tweet, and Mikael Emtinger came up with the excellent name: Landing Page Product (LAPP). A product that is fully enjoyable on its landing page.