Receipt-scanning service Shoeboxed just launched a new feature that automatically files scanned receipts into one of 15 expense categories. These include groceries, gas, and travel expenses, which you can view simply by clicking on them. Users can also create their own expense categories, although there's currently no way to have the service auto-tag expenses by keyword.
In addition to new receipts, users will find a good number of their old receipts categorized. Dan Englander, Shoeboxed's VP of Communications says some may not get the tagging treatment if the system can't find a match, but that a "large majority" have.
Users of Mint.com and other online banking services have been enjoying auto-categorization for some time now, but keep in mind these places are getting the information digitally. Shoeboxed must first scan your receipts then run them through optical character recognition. The categorization is not just for the scanned receipts though; any online receipts you "CC" Shoeboxed with will get tagged too.