How to hallucinate using ping-pong balls and a radio

boston.com — Do you ever want to change the way you see the world? Wouldn't it be fun to hallucinate on your lunch break? Although we typically associate such phenomena with powerful drugs like LSD or mescaline, it's easy to fling open the doors of perception without them: All it takes is a basic understanding of how the mind works. Jan 12, 2009 View in Crawl 4