<Usual disclaimers about breaking your pi etc. apply>
I have just completed a successful hack to use this PoE module:
http://uk.farnell.com/infomart-it-solut ... dp/1902521
to power my pi direct from a Netgear FS108P PoE Ethernet switch
I could have replaced the Ethernet socket on the pi with a magjack PoE replacement such as:
http://uk.farnell.com/stewart-connector ... dp/1901301
but I fancied a challenge. It turns out to be possible to disassemble the Ethernet socket on the pi, to replace the quadpack 75ohm resistor with 2 0603 75ohm and to bring out two wires from the mid points of the TX and RX transformers. Hook these into the PoE module and Viola! working PoE.
Photos and further details available on request.