> P.S.  I know USB is a bus, not just a port---does anyone
>       know if a PCI-USB bridge (like an adapter card) will
>       ever come out?
Yes, I've got one.  Check out www.usbstuff.com, they sell them
for about $100, I think.

ohci0 at pci0 dev 13 function 0: Opti RM861HA (rev. 0x03)
ohci0: interrupting at irq 9
ohci0: OHCI version 1.0, legacy support
ohci0: 2 downstream ports
usb1 at ohci0
uhub3 at usb1: Opti OHCI root hub (class 9/1) (rev 1.00/1.00) (addr 1)

        -- Lennart