what to do when your two year old keeps on escaping

Last week this little guy took off on me three times. He has a cute little face but do not let that fool you for one second because that is all that he needs to get out of the door. During his waking hours I clean for about 4 minutes and then I check on Tyler. I run to the bathroom and put my hair in a ponytail because that is all that I have time for, and I go and check on Tyler. I throw a load of laundry in the wash and take care of the baby and check on Tyler. To relax I play a short piece on the piano and then I go and check on Tyler. You can get the my drift. He is constantly on my mind and with his energetic and daring ways he is a constant concern.
If he wants something, he will be determined to get it at no cost. Therefore, I have to choose my wars with him very carefully. Before we enter into battle I have to decide first of all if I have enough energy to win the battle. Secondly, I ask myself repeatedly if the issue is really worth a battle. Thirdly, I make a quick check list of possible reinforcements, and I make a plan B.
The problem is that he comes up with his plan C before I can move on to my plan B and with a triumph smile he wins once again.
Last week, I quickly threw my hair up in a ponytail, brushed my teeth so quickly that it is embarrassing and made my bed. I rushed down stairs to answer the phone and as I was answering the phone I started to look for Tyler. It was my mother. "Are you missing someone?" she asked. " Nope" I answered as I continued to do a quick search for the little guy. (with him you need to look up high too because he can scale anything)
All of a sudden I heard a little voice jabbering to me on the other end of the phone. In under four minutes Tyler had managed to run to my parents house which is about 2000 feet from our house; with his winter boots on backwards and carrying my van keys. (It takes Nate 2min and 13 seconds to run from house to house). I was shocked and so where my parents when they heard their front door open and a cherry, "Hi grandma!"
This was the first incident. He did it later on in the afternoon carrying a whisk, and again a few days later in the freezing cold with no coat on. Each time I had no idea that he was even gone.

So this is our solution. A Proximity Sensor, also known as a Wireless Leash. I zip-tie the sensor to his belt loop each morning and when he goes out of range, the gadget beeps and my Ipad also beeps. There are a few glitches in this solution - like he needs to keep his pants on at all times, but for the most part it works. We bought it on line and had them send it to us with the fastest shipping possible.
Now I am hoping that they will invent a gadget that will tell me what his next move will be!