Homemade energy/electrolyte drink:

In one cup or a bit less of boiling or hot water, dissolve a pinch of salt and a tablespoon or three of honey (you'll arrive at the proportion for your taste). Add about a teaspoon lemon and/or lime juice for flavor. Put ice in bottle(s); pour mixture in bottle to cool. Top up with cold tap water if needed.

Considerably more pleasant (and cheaper!) than Gatorade, which frankly reminds me of overly sweetened, artificially flavored saliva. Ick.

Need more potassium? Carry a banana in a jersey pocket (and eat it during the ride, wiseguys).