For a moment I thought this was a new menu item in Snow Leopard. But no. Apparently I’ve been glossing over it for three and a half years — “Save PDF to Web Receipts Folder” was a new menu item in Tiger. Just because it’s old, however, doesn’t mean it’s not a clever idea. Though I still use Yojimbo to store all my receipts so I can tag and, if necessary, encrypt them.
(Tip: If you have used, or start using this automator workflow, you may want to read this first, so you don’t overwrite previously saved PDFs.)