Noticing a lack of applications for this type of device on the PC side, I decided to write my own. This works well with voice control applications that have the ability to execute external applications (via the included client utility).
Included is the ability to: set up to two timed on/off schedules per day for each device; set up motion sensors to trip specific light or lights and then turn them back off after period of no motion; use the included client application to send remote commands to the control center to turn on/off or enable/disable automation for specified lights or sensors.
Note that some antivirus software will see both applications as "suspicious". They've been scanned to be free of viruses, but do open port 1005 for communication.
This software is only useful if you have at least one Belkin WeMo switch.