I have been practicing vipassana meditation for over a year now on a daily basis (lately twice daily) In the past I tried to meditate while vaporizing cannabis at the same time, but never had the concentration to follow through. Now a year later, having developed my concentration further, and developing a new technique, I have found out that a controlled cannabis experience can be very different than the regular relaxation normally found from marijuana. I find that if I start meditating for 10-20 minutes and then after my calm concentration has been cultivated I start vaporizing, while maintaining concentration. Amazing visuals, sensations, and emotions pass through your mind. Feeling as if you are flying, seeing a dream play out without actually being "in the dream", colors, patterns, it is almost psychedelic! The best part of it though, unlike real psychedelics is that you can stop the show at any time by simply opening your eyes. Also if concentration is kept throughout the sitting upon ending the meditation you feel high (normal high) but you retain damn near close to 100% of your mental abilities! No mental fuzziness! But the body and mind are high! It is truly a wonderful experience. Sometimes I sit for an hour, sometimes just 30 minutes after the vaporizing is complete, but all I can tell you, is that if you have been smoking marijuana for a while and are interested in achieving different states of mind without using other drugs, meditation is your friend.