Pretty much any situation that would enlist the use of any type of alcohol, usually rum, vodka, tequila or in extreme cases (if your trying to kill something) even grain alcohol. The alcohol is used to substitute some of the water or fruit juice used to solidify the jello shot mix.

An American mathematician by the name of Tom Lehrer is thought to have been the 1st to craft the jello shot in the near beginning 1950s while working for the NSA, where he developed vodka jello, this was his genius idea to sneak alcohol onto the military base with out any of the commanding officers getting wind to it.

The mightiest concentration of alcohol is somewhere in the region of 18 and 21 ounces. of vodka per 3 oz. pack of jello powder (what ever flavour), or around 30% alcohol liquor.

Alternatives

A few gelatinous desserts can be manufactured using agar instead of jello, allowing them to set far quicker and at higher temperatures. Agar is a vegetable additive that is produced from seaweed and is very useful in jello shot mixes for it rapid setting times. This is also a good choice when making jello shots for vegetarians or vegans. Agar is really closely tied to pectin, as well as a few other gelling plant carbs than it is to standard jello.

There are different alternatives to vegetarian jello, this is known by the name carrageenan. This alternate will solidify faster than the agar, this makes it popular for kosher cooking. Though it, too, is a type of seaweed, it does not have the same bad sort of smell when being cooked that you would sometimes find when you cook with agar Chemistry

Fresh pineapple should really be avoided when making jello shots, it contains the enzyme bromelain which must can never be allowed to mix with the jello shot mixture as this enzyme will prevent the jello from setting, this enzyme is common in most citrus and tropical fruits. Papaya and pawpaw contain the enzyme papain, kiwi fruit contains actinidin, and figs contain ficin- all with similar effects. Cooking destroys this enzyme, rendering it inert so if you want these jello shot flavors get the other half to fire up the cooker.