How do you disassemble the Lego when they are first acquired? My guess is that, buying bulk Lego, some of them will already be snapped together. Is that a manual first step, or do you have a technique to separate them automatically?
My most hated parts to separate are a flat dot on top of a regular dot. Second runner-up is the 1x1 plate on top of a dot, which is common in the Minecraft sets. I'd pay for a machine just to separate these for me!