For many IT managers USB port connectivity can still pose a large threat to company security.  One quick down-and-dirty method is disabling the read and write from any system USB port.  This can be done through a quick registry edit.

Here is the full Microsoft article explaining how to disable a USB port (link). Note:  This is a registry edit so be sure to backup your registry first and know how to restore it in case something terrible happens.

To disable the access to USB port, in windows XP and 2000:
1. Click Start, and then click Run.
2. In the Open box, type regedit, and then click OK.
3. Locate, and then click the following registry key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\UsbStor
4. In the right pane, double-click Start.
5. In the Value data box, type 4, click Hexadecimal (if it is not already selected), and then click OK.
6. Quit Registry Editor.

To re-enable a disabled port:

1. Click Start, and then click Run.
2. In the Open box, type regedit, and then click OK.
3. Locate, and then click the following registry key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\UsbStor
4. In the right pane, double-click Start.
5. In the Value data box, type 3, click Hexadecimal (if it is not already selected), and then click OK.
6. Quit Registry Editor.