<i>So if you have a breadboard and a USB to serial adapter, you could build the bare bones version of this for about $6 and maybe break the bank at $15 if you had to buy everything. </i><p>I&#x27;ve got a usb to serial adapter just sitting here, definitely trying this project for just $6<p>Wish it only needed 5V supply, I have endless phone chargers laying around from 500ma to 2a