I'm using a $29 WIZ125SR two port serial to Ethernet board for my Paramount ME and Pyxis rotator:
http://www.shopwiznet.com/wiz125sr
I put the board on 1/8" standoffs and made a clear acrylic plastic case for it using a rotary tool. It works perfectly with TheSkyX. Just have TheSkyX connect to via IP address and PORT numbers instead of COM ports.
They also have a 4-port model for $99.
Works well so long as you don't mind making your own case like I did.
I have not yet tried any of the USB IP hubs. Some guy on Cloudy Nights swears by this one:
http://www.usbgear.com/computer_cabl...53%2C210%2C212