With a Linux box and the Common Unix Printing System (CUPS), you can set up a virtual print server that will output all of its jobs to PDF format. Why might this be useful? From the linux.com article:
When you buy stuff online, virtually every site provides a receipt, which you may want later if the order email is lost or if you need to send in a receipt for expense reports. However, you may not want to print all of them out just to keep them around, and Firefox only supports writing to PostScript, rather than PDF.
What’s nice is that you can print to your PDF making device from any Windows, Linux or Mac desktop. This provides a mechanism for consolidating all of your receipts and digital paper assets into one place, which ought to come in handy as you pursue the goal of having a paperless office.