I still have my slide rule but I lost the leather case it was stored in. Smart HP calculators were okay to use during tests, the only trick was being able to afford one. I had one of those Sinclair computers and soldered a keyboard to it, didn't like the little keyboard. One of these days I will have to get a bluetooth keyboard for the phone. I have several black model 500 rotary phones, they work great when the power goes out. Might even have a yellow one somewhere. Couple of old electric fans with a simple screen made of a few 16 gauge wires covering the blades, you can stick your hand inside the cage. I guess it was there to protect the fan blades.