Yum! Nothing goes better after a day of munching green, followed by a scoop of feed pellets, than a good salt/mineral lick. Fulfills an RDA requirement, I'm sure.
In hot summer months, when the temps are extreme (close to 100 or more) and just standing there makes the horses swelter, I've been known to add crystalized electrolytes to their feed. I'm sure if I mixed it in water, it would taste JUST like Gatorade.