Optus PrePaid Wireless (GSM/3G) Broadband, routed from a usb dongle via internet connection sharing to the ethernet port, to the wan port on a wireless router, to my lappie via 54Mbit wireless.
I can play on littlewhiteys mta race at 450 ping, but it tends to peak at 650... luckily they don't seem to boot me - some of the oldskool there, amidst my apology, asserted that it actually wasn't lagging too bad.