So plan ahead, and try to escape-proof the reptile room, lab, or your whole house. Put screen over vents, tape up the places where pipes enter floors or walls, try to find and eliminate other small openings in walls and around windows and doors, etc. It'll pay off when even little escapees eventually turn up, sometimes weeks later. They might find it before you do. Inside, under, on top of things.
Some species typically climb, others squeeze into and under things.
Several times I've recaptured rat snakes that squeeze through the bars, eat, then can't get out of the mouse's cage.