how bout hydrogen peroxide? H2O2
I’d call that inadvisable, particularly if we’re talking about the pure form and not an aqueous solution. H[sub]2[/sub]O[sub]2[/sub] really wants to get rid of that excess oxygen, and whether by oxidising your stomach lining or just decomposing and liberating lots of gas in your stomach, it is not really going to make you feel very happy either way.
I just noticed that the OP’s question was asked on alt.fan.cecil-adams almost exactly ten years ago. 
The answers in that thread are mostly the same as in this one, though there were few more candidates listed there that haven’t been mentioned here: isopropyl alcohol, gamma-hydroxybutyrate (GHB), polydimethylsiloxane (silicon oil), and olestra. Note that these are “safe” only in small quantities, and even then may have unpleasant physiological effects.
It’s what it is used to cause vomiting in dogs. I would imagine it could work similar in humans, but I have no interest in trying.
Assuming we’re still talking about the pure form, no it isn’t; orally administering pure hydrogen peroxide will kill dogs (or humans, for that matter). The hydrogen peroxide used to induce vomiting is diluted to a 3% solution.
True, and as it should be. OTOH, most of the compounds mentioned in this thread have included “diluted with water” or “in small quantities”. Even though I agree, the original question was for undiluted liquids.
glycerine, though it make you poopy if you drink a lot
Not ambiguous at all. A pure compound. Not any salts or acids dissolved in water. Just any chemical that is liquid at room temperature and 1 atm pressure, and just the pure chemical, every bit of it made up of the same molecular structure. No solvents or solutes.
numerous other alcohols that are similar to propylene glycol
any of the mor specific chemical fractions of mineral oil that make up the lion’s share of the oil? Probably some high-n petroleum based oil?
I did drama tech in high school, and our director was always talking about how safe fog fluid was. Any time someone asked if the fog machine would be an issue with their asthma, he always said that there was nothing harmful in it and you could drink a glass of fog fluid if you wanted. IIRC we used regular fog fluid and not anything special.
Most likely propylene glycol or glycerin. Propylene glycol is the antifreeze that is used in RV plumbing so the pipes don’t freeze in the winter.
Put some of either in an electric frypan and see what happens.
Some things are solids, so drinking may not be the preferred route unless dissolved on a solution.
NaCl, salt water; KCl, similar. you can ingest both to certain limits
I wouldn’t drink dihydrogen monoxide. That’s stuff is deadly.
Heh; Water, Archer fan…