Hi,
here's a nice solution to connect an external DVD Drive to a Q40/Q60:
Obviously, USB could not be used, but there is s standard for external SATA drives with integrated power supply, called eSATAp.
By using an IDE-SATA converter in connection with an eSATAp slot bracket, the Q60 can be equipped with such a port.
Most external drives are USB, but some are eSATAp. I bought one from DELL and it worked immediately.
Peter