I was still in my early twenties, went out partying the night before, eventually decided that going to sleep wasn't going to work anymore so I just stayed up. Met a friend who was going to help me prep early in the morning and had the world's most hungover coffee while going through some questions with him. A couple of hours later I was showered and dressed at the interview.

Other than feeling like death I actually did ok, didn't get the job initially but got shoulder tapped for the job a few months later so it worked out.