The parallel port is much underrated; it may be old but it's not dead yet. Where data rates don't need to exceed a few megabits per second, it is a very efficient way of communicating between PC applications and external hardware. Much simpler to implement than a USB interface. We have seen a requirement to add a parallel port IP block into a system FPGA to support a legacy application, but most applications centre on a parallel port dongle. This allows PC applications to control and monitor external hardware through a range of serial interfaces.