Implementing Backpack/Lighthouse Email Input Feature

Howdy,

I'm working on implementing email input for a Web app. I've got the basic email stuff working but I want to use an addressing scheme similar to Backpack or Lighthouse - where you assign randomly chosen English words to construct a semi 'secret' address for each 'page'.

For example, a Backpack page may accept email send to the address jive23talking@mydomain.backpackit.com

I'm curious if anyone has implemented this sort of thing and if so, if they had written it up. I'm sure I can figure it out but I'd be interested to hear about other folks gotchas while implementing.

Thx.