How interesting to call skills tools, for example, you are right. One of my best tools is my creativity, which I have improved over the years thanks to another one which is inspiration, I get inspired by many things and it is something that is always active.
But if we talk about physical tools, my computer is my great tool and the programs I use, I must always be perfecting and practicing them, otherwise I forget them a little bit. Like a program that I haven't used for 7 years .... if that I have forgotten, but I have already installed it to refresh and retake the use, bring it to the memory and improve myself.
The program is called Corel Draw, to make drawings with vectorial design.