There are other options but these are the ones I think might be easiest to implement. Zebra Web Printing Solutions
Cold Fusion is a web application, similar to PHP, Python, Ruby, etc. I was thinking it would be easy to have Cold Fusion send an email to and email server and then have the QLn log into the POP3 email server and check for emails to download. I can't get this to work. I put a dummy email in the inbox that should print a tag when downloaded. I'm not sure I have the QLn set up with the right configuration to log into the email and download it (not sure about SSL authentication, ports, etc.). I was wondering if there was a way to debug what is going on when the printer tries to go out and log into the email server.
I will look into connecting using a TCP socket, but not sure how to do that when the printer is on the office network and the Cold Fusion server is in the cloud.