The HP LJ4050 does support IP printing, and though the JetDirect card that allows this is kind of pricey it works great. My office has a mixture of 4050s and other, more recent HP printers, all networked for sharing, and they are ery reliable. Generally (at least with the PCs at work) all the using machines need is the proper driver for the printer, and JetDirect takes it from there.

(I'm kind of embarassed that I spelled Farallon wrong-that sure explains why I couldn't find their site, though.)