Very few handheld calculators support pure binary operations. If you have the high end ones binary operations are supported but you need to dig in to things to get them working the way you want them to be, which makes manual hand calculations better. One solution is to use the windows calculator, with just a push of a radio button viola! From decimal to binary but this time you need a computer to do simple binary operations. The best solution? Build one!
Implemented in an ATtiny2313 microcontroller this binary calculator could evaluate binary functions such as NOT, OR, AND, XOR, addition, subtraction, multiplication, division and modulo – neat huh? In addition to the functions it can compute, this calculator has bright blue LEDs for the binary display. As it turned out ATtiny2313 isn’t that small after all.