Crazy Backwards Alphabet (yes, it's a little bit "Where's Waldo"-ish this time, but they are in there -- two of them at least!)
Mick Taylor - Tropical Disease on Mushroom Records (a boot recorded during Exile On Main Street sessions) -- I saw this back in the mid-80s, meant to pick it up, but when I went back for it, it was gone. Will finally be getting a copy next month (a birthday gift!).
This is mental. I want this record. But seriously, the following album came out on the Pilz label (pilz is German for mushroom). Their center labels had their distinctive logo design...
I don't know about Album covers but Australia had a record label called MUSHROOM RECORDS.. picture of a mushroom on every record!
I posted an example of one of Australia's Mushroom Records' releases on page 3 of this thread -- not the album cover, but the label, which is illustrated with mushrooms.