First, thanks to the mods for permission to post this.

I'm involved with a team presently developing an expense tracking app called ReceiptLoader (on the marketing end, not the development end).

It works using the camera. You take a photo of the receipts in question, and in a few seconds (or minutes depending on the connection), the receipt will be logged in the app with an image of it.

Caveat: So far it only works only on a single currency, but otherwise it works.

If you're interested, sign up at http://www.receiptloader.com/

Once this works, the next priorities are Android, WP7 and Blackberry.