I was using this widget:
http://linestreet.googlepages.com/sleepdisplaywidget
It just sends my display to sleep immediately. Since I switched over to AirPort wireless, whenever I send my display to sleep and then wake up, my AirPort Express is wonked out. I need to unplug it and plug it back in to reset it.
I would try some more troubleshooting, but I'm bedridden right now, and it's difficult to reset my AirPort when this happens.
Anybody else ever have this issue?