A friend of mine just finished growing a batch of shrooms, and I had a couple of exhausted rice/vermiculite cakes left. I know that eating colonized cakes to shroom is nothing new - but to do that, you can't use vermiculite, or you'll have some pretty interesting bowel movements for the next few days.
For him to just throw away the cakes seemed sort of wasteful though, and we live in a very arid part of the country, so it wouldn't do any good to plant them outside (and it's too cold now, for that matter).
So just to see if anything would happen, I cut one of the cakes (1/2 pint) into cubes and boiled them in about 2 cups of water for ten minutes. I then ran it through a coffee filter, and made some hot chocolate with the resulting tea.
I wasn't expecting much, but I was shrooming all day, much more powerfully than when I have eaten six or seven medium-sized shrooms. It was probably enough for two people to shroom pretty decently. Anyway, I just thought I'd mention it.