According to Men's Health, you can gauge how done your steaks are by comparing the elasticity of the steak to the way the meaty part of your thumb feels as it progressively flexes.
It works like this: You touch your thumb to your index, middle, ring, and pinky fingers, and the further you reach, the harder your muscle becomes. Apparently this should match up relatively well with rare, medium rare, medium, and well done steaks as you work your way from index to pinky. With a long summer of barbecuing ahead, this tip should come in very useful!
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