ProOnGo let me know about their current free public beta. They allow you to take pictures of your receipts and upload them to their service for later access. I guess you can already do this with your BlackBerry camera and offload them yourself but this is automated with easier ways to export the images.
NOTE: Sadly right now the app only supports the Storm due to its sharp camera but 8900 support is already in closed beta. Just expect it to support 3.2 Megapixel camera enabled BlackBerrys.
Let us know what you find!