I did. In my "The Last City" campaign, The River of Filth is pretty much a fixture, having replaced most of the normal thoroughfares through the destroyed neighbourhoods as the main means of travel (this despite being people with Otyughs, Trash Ogres and...yes...Crap Golems)
I created a Filth Golem, also called a Golem, which was made of congealed feces and other matter. Had a breath weapon consisting of a spray of sewage water and could cause disease as a secondary effect when causing damage with its fists. Unfortunately I don't have its stats on me right here.
Hmm. Can't say I've heard of a Feces Golem before this, but it brings up all sorts of possibilities regarding secondary infections and infestations resulting from a successful attack by the creature - and even resulting from a successful attack by the PC's. The splatter effect
Not to mention the possibility of nausea or weakness from the overwhelming stench of the creature.
I wonder if an earth elemental was summoned in a midden or similar sewage environment, wouldn't it effectively be made of the materials of the environment? Elemental with disease damage, etc etc. I'll have to ruminate on that one...
Hmmm... I just got off the pot in the bathroom, it seemed like it still moved, so I guess I just created one.... or does that not count???
(on a side note: what kind of wizard/cleric is a sick enuff puppy to want to create such a thing....)
Some special powers come to mind:
Cloud of noxious gas (causes fainting and temporaty Con loss)
Sonic (fart) attack (can cause buildings to crumble)
Spew doodoo (stickiness creates a penalt to Dex)
Jet of diarrhea (sp?) (also called 'diarhea disaster')
Swallow whole / engulf (eeew!)