If you have an empty PCI slot in your PC, then you can buy and install a PCI-to-USB card. This card offers both USB2.0 and firewire or only USB2.0 connectivity. It comes with 5 or 6 USB 2.0 connectors. And you do not even need drivers because Win XP sp1 or sp2 has the drivers.
You are not limited to using a USB hub.
For notebook users, there are PCMCIA cards offering USB connectivity.
My old PC had only USB 1.1 connections. I bought a PCI-to-USB 2.0 card and made my PC USB 2 compliant. I even disabled USB on the motherboard and used only USB on the PCI card.