Apple has released the SDK for the iPhone.
Honestly, I think that it is going to be the revolution. The iPhone is a MAC OS. Same platform but handheld. Believe me, there will be a before and an after of this.

drop.io enables you to create simple private exchange points called “drops.”
The service has no email signup and no “accounts.” Each drop is private, and only as accessible as you choose to deliberately make it. Create multiple drops, add any type of media, and share or subscribe as you want. To make a drop just click the big red button that says ‘drop it’