I've previously posted my single pin ultrasonic driver.
I also have a quad ultrasonic driver that's not abstracted from the 1024 2008 robot code entirely (as my previous single pin single ultrasonic was). I'll be releasing my quad ultrasonic driver as early as after ship date or as late as mid season.
Just to give a few specs, my quad ultrasonic driver (usdriver2.c/h) can read up to four simultaneous measurements from four parallax PING))) (or similar) ultrasonic sensors. They can be fired together or in any combination or sequence at any time (provided the individual sensor is not busy). The system makes use of digital I/O pins 3-6 and is not reconfigureable to any other pins, and also uses TMR1. This, also, is not reconfigureable.
If there is enough interest in this driver i'll make it more of a priority.
-q