Since I got a MacBook Pro for work, I've been annoyed that I only have 1 power adapter for it. I have a couple of MacBook ones, but I don't want to use them with the MBP. I have a Kensington 120W Universal Air/Car/Home power adapter, but unfortunately, they don't make a magsafe smarttip for it. The Googles told me taht I could make my own, so I followed this guide to make a magsafe cable for it. It works! Probably wastes some juice as I have it run at the 18.5V max magsafe voltage all the time, but it works and means I don't have to another Macbook Pro adapter.