This device type exposes two attributes that you can use:
“power” - which is the current power consumption in watts (W)
“energy”- which is the total consumption of power in (kWh)
The “power” attribute could be used with a SmartApp like Laundry Monitor by @sudarkoff or Yet Another Power Monitor to trigger a push message, text, or something else when your washer or gas dryer is done.
The “energy” attribute could be used to monitor the cost of whatever is attached to the monitoring switch. If you had energy rates that vary by time of day, you could write an app that sends a message if a device is run during peak hours, or turns off the switch during peak hours and turns it back on when electricity is cheap.
Hope that helps.