(Adrian) The HP Procurve switches are pretty shiny. I'll get prices next week.
1800 series: http://h50229.www5.hp.com/web/hp/procurve/au/products/switches/ProCurve_Switch_1800_Series/overview.htm care available for $560.
2800 series: going to be more expensive, but they have a -nice- CLI and I've never had one die one me: http://h50229.www5.hp.com/web/hp/procurve/au/products/switches/2800_series/overview.htm however they cost $2400.
Gigabit cards are now $12 each for realtek 8169 ones - pick up some for the various machines as well? The thinterms will require PXE support, which means using a Marvell chipset which cost a bit more.