The earliest memory that I have of a ruler is of my ruler-brandishing teacher, reprimanding me with it. As time flew by, my carpentry skills in college took a toll, again the blessed ruled wouldn’t side with me. Now at this stage, when I feel I have conquered all fears, the trepidations of the ruler is back to perplex me. Greg Blonder is a gifted inventor and has conjured up a prototype of a clock that uses two rulers that slide. I was bracing myself for another bamboozle, till I saw the video of the clock. The Slide Rule Wall Clock is very easy enough to decipher; separate rulers feature the hours and the minutes and move over each other as the time passes. Time is read at the point where the two rulers meet at the red line. Interestingly two mindstorm servomotors using LEGO Mindstorms have powered the clock. Kudos Greg, for this interesting concept.