Taking psilocybe mushrooms and MDMA (ecstacy) together. Actually regarded quite highly within the drug subculture. The effects rarely last longer than 8 hours. The effects of the MDMA lend a very upbeat feeling to the user, usually resulting in a positive mushroom trip. Because MDMA is a fairly "reliable" good high, but mushrooms aren't (there can be bad trips), the MDMA high helps to stabablize the mushroom trip.
The practice of mixing psilocybin ("magic mushrooms") with MDMA or ecstasy. This often creates an amplified effect even if the user only took a small amount of each drug.
"Dude, I was rolling so hard on that E last night..."
"Yeah, but not as hard as Susie; she was hippieflipping on ecstasy and shrooms at the same time!"
Taking extasy and mushrooms in a combination with each other. The tripp can last until the person goes to sleep(up to several days). Highly discouraged by most veteran drug users.