What's the longest you've gone without sleep (and why)?

I can't sleep day long

I think it was about 3 days, and that was because I ran out of my antipsychotic meds and had to wait till my next payday before I can go out and buy some. 

48 hours. a dear friend of mine got hurt in a car accident, he was rushed to the hospital to be operated on. I waited around the hospital for 48 hours before I was allowed to see him. 

About a week because I was a drinker at the time,

I stopped drinking for over 30 years now.

Went to L.A. back in the early 80's and went clubbing, dining and more for about 21/2 days, fun.

Almost 7 days while on a LRRP.

2 days when I had strep throat. It was painful to lay down and every time I tried to swallow, it would wake me up, so I just stayed awake. 

Almost 2 days. Insomnia during the night, coffee during the day, more insomnia due to the coffee and on the second day I finally fell asleep.

Back during the Tet offensive in Vietnam, I was up for 3 days straight !   

2 days.............