Here's perhaps a new one: I connected my old fashioned doorbell to a spare input on the Konnected alarm system. Instead of triggering an alarm, SmartThings is configured to send a notification to my mobile phone. Now when I'm in the backyard, or in my workshop, I won't miss the doorbell!
If you are interested in the details: I used an MC-38 magnetic reed switch with the magnet half moving with the cable inside a section of 15x10 mm cable duct. The reed switch side is just mounted on the outside of the cable duct. It was only tricky finding just the right screw to attach the magnet to the cable so that it could still be adjusted.
A great way to use a spare input on Konnected!