Luke Perman of Hoven, South Dakota, figured out how to use a spare cell phone and the Skype mobile app to monitor water tanks or electric fence energizers far from home.

He says the price of running the system is a cost savings over driving to distant locations just to check on such matters.

"I set up a smart phone facing a water tank I wanted to keep a close eye on. I installed Skype, made a new account, and set it to auto-answer when I call it from my other Skype account," Perman explains.

"Total cost was about $50, plus $15 a month to activate the phone on our mobile plan through AT&T. If it saves me one hour of driving around each month, it pays for itself. The nice thing about using Skype with auto-answer is you don't use much data on your mobile plan. I looked into several other platforms and this seemed to be the best one."

Here are the five things Perman explains you'll need to accomplish the same thing:

1. Android smartphone - It can't be an iPhone, there's no auto-answer function on the Skype iOS app. I used a Samsung Galaxy Rugby Pro, which is waterproof. It only works with GSM carriers like AT&T or T-Mobile, not Verizon. There are others that would work. Mine cost about $30

2. Solar battery pack/charger -- 300,000 mAh cost less than $20 on ebay.

3. Fish-eye lens clip to provide wide-angle view. Costs $5 on eBay

4. Silicone to seal up the wire between the phone and charger.

5. Something to mount the unit on and protect it from the sun and hail.

To make it work, Perman says to set the Skype app on the phone so it only accepts calls from the contact list, then have only your main Skype account as a contact, unless there are other people you may need to view it.

Since the original setup, he has made some changes.

"I am now using an app called Alfred," Perman says. "I still use old phones with Alfred when I have Wi-fi and 110-volt power. I had trouble keeping the phone charged using a battery, but that was a hardware problem. I bit the bullet and bought a few cameras through Barn Owl. More up front cost, but the data rates are very reasonable. They are working well."