Andy Farrow was in an English punkband called Living Dead when he was a teenager. 
This is a split 7" they released in 1993 with Destination Venus.

This is a 1994 demotape from Swedish band Hypocrite.
Mikael designed their logo together with David Isberg under the name "Dave and Mike Opeth prod.". 

MTV-USA used this tape to air the video from The Grand Conjuration on tv. 
So this is an extreme unique item which it's exsistence is not publicy known by much people. 
As far is i know there are only two of these tapes around on the world. 

An original demo-cassettetape from Crowley.
This was the band formed by Mortem Svanborg (vocals), Martin Persson (bass), Micke Borgström (guitar), Dan Nilsson (guitar) and Rille Evén (drums).
These are the men who were in Opeth when Mikael was asked to play bass. After an arguement they all left and started Crowley.
After a few years of hunting i finally found a copy of their first and only demotape "the gate".