HOWTO Use the Laserjet 6P
The printer is an HP LaserJet 6P. It has a little Hawking parallel printserver stuck to the back of it. The printserver's IP address is 10.13.0.99
On a Mac, this is pretty straightforward. Just know that "port 9100" is the protocol to use, and if it gives you a choice between PS and HPGL, use HPGL.
On a Windows box, you need to ignore the temptation to click "add a network printer", and instead, "add a local printer", then "create a new port", then port type "standard tcp/ip port", then enter 10.13.0.99, and everything else should be sensible. If you are using Windows 7, there is no driver specifically for this printer. The LaserJet 2200 PCL5 driver at least prints the Windows test page correctly (have not tried extensive use).
Manual duplex (printing one side of a bunch of pages, then flipping the stack over and putting it back in the paper tray to print the other side) usually doesn't work, and results in paper jams, because the paper curls too much after the first pass. You can do it by using the front page-at-a-time paper slot for the second pass.
If you find that some of your graphics don't print the way you expect them to, go into Advanced and either step the resolution down, or change "HP/GL" to "Raster". This will make the printjob larger and thus slower to transfer over the network, but it's never failed me.
If things aren't printing, don't just randomly mash buttons on the printer. This makes it spit out test pages, which wastes paper and toner and just serves to tell you that the printer is, in fact, on and capable of printing. Instead, see http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=bpl04061 and try to actually troubleshoot the issue.
Please don't change the printserver's IP address or configuration, it is not at fault.