I was interested to hear of the launch  of Labelgrid recently.  This is a new open source project (GPL licence) to design a web based label printing software stack to design and print labels in a browser rather than the typical client based software.  There  will be a number of challenges in this as the authors point out on their webpage, but I thin its a really interesting idea if they get it to work well, and I wish them all the best in the code development .  You can see a demo here.