No it's not liquor but
1.Scorpion Venom 
$ 39000000 per gallon
Scorpions use their venom to kill or paralyse their prey and as a defence against predators. Of the thousands of species of scorpion only 25 have venom that is deadly to humans Why the high price Protein in the venom can be used for the treatment of conditions such as rheumatoid arthritis inflammatory bowel disease and multiple sclerosis.
2.King Cobra Venom 
$ 153000 per gallon
One bite and pretty soon the victim suffers from symptoms including blurred vision vertigo drowsiness and paralysis before falling into a coma Death soon follows due to respiratory failure It’s not all bad though cobra venom has been used for many years to treat pain it was once even thought to be an aphrodisiac.
3.LSD 
$ 123000 per gallon
LSD or Lysergic acid diethylamide fuelled the psychedelic-sixties You wouldn’t normally buy it by the gallon unless you wanted to give a small country hallucinations for a month in fact a gallon of LSD would be enough to send about 55000 people on the trip of their lifetime.
4.Mercury 
$ 3400 per gallon
Mercury is a liquid metal which was traditionally used in medicine and the production of thermometers Due to the element’s toxic effects alternatives are now used Mercury is the only metal that is in liquid state in room temperature.
Hope you didn't knew that.