Most potent strain I have had was a 'thai stick' back in the late 90's. I remember when I got it I thought I got ripped off. It was just brown looking, no real crystals, and lite smell. It was $60 and 1/8th which was the going price for the good stuff at the time. Me and a friend were both thinking it was just some higher end mec weed that wasn't bricked ... boy were we wrong. It is the only time in my life I have truly had what I would call a '1 hit wonder'. We get back to my place, load up a bowl, each take 1 hit from it, and both of us were floored for about 4 hours... our heads were in la-la land. We couldn't walk, more like crawl if we wanted to get something. It was like being as drunk as we have ever been as far as trying to move.. and then it took 20 minutes to go 20 feet to get a drink of water, and in that time had forgotten 20 times why were were crawling towards the kitchen. I have had some great stuff over the years, stuff that looked, tasted, and smelled much better, but nothing has ever come close to how hard 1 hit of that hit us. To this day I have never come across that strain again, or even know if it really was that strain, I just know that while I don't remember much of what happened that night, what I do remember clearly is it was the most intense hit I have ever had. I tend to think I have a good tolerance, I can go through an 1/8th on a bad day, or good day, however you look at it, but the thai stick was on an entirely different level.