iPhoto printing
Apparently, my computer announces the fact that it has a printer available over the network. Hooking the mac mini up to the same subnet means that a printer labelled "hP" shows up in the "Shared printers" drop down. This allows me to print from any mac on the subnet with no configuration whatsoever.
iPhoto makes printing photos easy: select a picture, click print, and choose the size you want. Apparently, the HP 670C series also does complete auto-detection of paper type, so I didn't even have to change any paper settings: it was all done for me.
I must admit that I have never found printing photos easier: Who'd have thunk that the most complex setup imaginable (printing from a mac over the network to a printer connected over USB via cups) would be the most efficient? Thanks to the ease of this task, I now have a full 8x10 of julie, from when she came to vote with me.