Randall goes thru a 2 gallon tin of Gatorade powder in about a week.

I found, by reading the ingredients and a bit of experimentation, a MUCH cheaper homemade version, that he says is pretty much the same in flavor:

for orange:
2 pkts unsweetened orange Kool-Ade or generic
1 pkt unsweetened lemonade

1 cup sugar
1 cup sucralose (brand name is splenda but there are storebrands. Make sure it is sucralose, not aspartame.)
1/2 tsp iodized salt
1/4 tsp fake salt (potassium iodide; there are several brands and generics)
1/4 tsp citric acid (you can find this in the Kosher section, listed as 'sour salt'

Mix well. Mix with water to taste.

I figured that the above costs about a dollar for a batch. The most expensive items are the sucralose (about $6 for a package that makes 10 batches), the unsalt ($2 or $3 for a small canister, but will make 40+ batches) and the sour salt (but I found a 5 oz jar for 99 cents). The sour salt/ citric acid is also usefull to acidify water to put apples, pears, or potatoes in, so they won't get brown; also you can use it in cheesemaking.

I guess you could experiment with other flavors of koolaid. You could use 2 cups of sugar, but don't use all sucralose, as the sugar is needed for the electrolytes to work.