Digital 8 tape camcorder. Since the camcorder manufacturers stopped supporting/updating the USB drivers for USB connectivity to get the video off the tapes (same with miniDV), and since you know you need firewire but no available slots to add a port, I think you have a choice:

1) Use a computer with a firewire port.

2) Connect the camcorder's analog audio and video to an "analog/digital converter", connect the A/D converter using USB to the computer. The video quality won't be as good as using firewire for the importing, but it is what it is...

USB won't work. USB-to-firewire cable/converter/adapters won't work.