I don't remember the name of the company nor the question but in the dot com era there was a startup in the central square neighborhood of cambridge which was n

I don't remember the name of the company nor the question but in the dot com era there was a startup in the central square neighborhood of cambridge which was notorious for asking candidates one of those gotcha "really hard to answer if you'd never seen it before" questions. The catch? Apparently that question was something which every MIT CS had seen before but wasn't frequently used elsewhere. Thus they were effectively filtering for MIT grads without being obvious about it.