In the most recent issue of D-infinity, issue 6, I wrote an article on various artifacts for Mutant Future. One of the catagories is formulae- substances the PCs can create by mixing and treating various materials that have been exposed to superscience, exotic radiation, mutations and such. So in a way, it is alchemy for post apocalyptic settings. The thing is that it doesn't have to be driven by intelligence. Monsters could perform it without understanding and there can even be instances of erosion or disaster based formulae just sitting around. One group of such formulae are goo pools. They can be found just about anywhere- in the wilds, in ruins, on roofs, on ceilings, under boulders and even on vehicles. Goo pools are discribed by their appearance, size, method of activation and power.

Appearance is color(s), opaqueness, consistency and possibly sound. I suggest taking a look at Appendix K in the first edition Dungeon Master's Guide if you have access to it.

Size can be deceiving as some are quite narrow in width and yet are very deep. I don't suggest a die roll for this, but if you want, say 1d4 X 1d10 for both width and depth.

Activation is usually done by coming into contact with the substance, sort of like a mystical pool. However there can be other requirements, sometimes in combination.

Powers can be anything you envision. Some are positive, some are negative and a few are both. Here are 20 examples to get you going:

It belches paralytic gas.

It forms pearls that glow when exposed to gamma radiation.

It expels most parasites and cures most diseases.

It repairs circuits of minor damage.

It is a narcotic to vegetable life forms.

It grows eyes on the bather. Those who see through these eyes are elsewhere.

It implants an urge to return home.

It extends a replicant's lifespan.

It dries as a membrane that amplifies sound.

It is addictive to fowl.

It is food for lightning children.

It alters the effect of magnets on iron (the iron or alloy must be placed in the pool). 50% the effect is stronger and 50% it is weaker.

It alters the bather's voice volume.

It dries as a stone that explodes in contact with water or other liquid.

It turns rust into a vital component of planar gate technology.

It is a sleeping ooze or other monster that shapeshifts to its normal form upon awakening.

It causes a mutation cascade.

It places a bather in stasis.

It overcharges power cells and basic androids. They gain some benefits before self destructing.

And here are a few example pools of my own:

8' wide by 4' deep; a gooey, glowing orange with green bubbles that hiss when popped; when exposed to loud sounds, it throws orange lightning that strikes everything within 50' and turns gold into water. There is no save but the lightning doesn't do any actual damage either.

5' wide by 2' deep; a dull yellow paste; those who touch it with bare skin become hosts to "electric ghosts" who transmit knowledge of the Ancients (use the Find the Path spell for ideas); if the host is slain in melee, the killer gains the ghost.

15' wide by 42' deep; grey water with silver specks; upon exposure to UV light, the pool flashes a code that will open the nearby vault door. Alternately, the pool places earworms in the heads of bathers; when sung together, these are the code that will open the door.

3' wide by 6' deep; metallic silver with gold bubbles that release smoke when popped; when the pool comes into contact with flesh, local police robots are alerted and the bather gains either the Prey Scent drawback or the spell Faerie Fire for 24 hours.

4' wide by 5' deep; appears as concrete and has a consistency of slime; bathers who are exposed to gamma radiation within 36 hours are safely fused with one artifact (determine randomly). In effect, the artifact becomes a piece of cybergear.

The difference between mystical pools in fantasy settings and goo pools is that the latter are much more susceptible to change. A blast of energy, wind swept nanites or even the sweat of a mutant bather can alter a pool's power.