Blue lobsters are a sign of good luck. They are rare lobsters that have a blue shell instead of a red one. I know, I know, duh. But some people aren't able to see the color blue because they have this thing called, "ADHD." Their hyperactive personalities don't allow them to see colors like normal people. So next time you find out a friend of yours has ADHD, you should just pat them on the back and say, "I'm so sorry."