An Auto Receipt Printing Application for MacOS. This application monitors a specific directory for new ".rcpt" files. If it finds one, then it will automatically send that file to the default printer.
The 10.8+ version has a monitor app that can be used to start, stop, and choose the directory to search for ".rcpt" files.
The 10.4 and below version doesn't have a monitor app but you can use specific commands to start, stop, and check on the daemon