I personally wouldn't go without sleep for over 48 hours. After 24 hours with no sleep, it's clear that it takes a toll on the energy which remains, and other factors. I found that I was unpleasant to be around with a lack of sleep, and don't find it enjoyable to go without sleep for long. I honestly don't see why people would want to go without sleep. What are you trying to achieve? Are you trying to prove yourself?

If there's a goal you're aiming to achieve, such as an experiment; I say go for it! Just be cautious of what you're getting yourself into.