Ah.. I wouldn't quite say soda & pop.. More like.. cola & pop. Cola is definitely a pop, but not all pop is cola. (corns are rat snakes, but not all rat snakes are corns, and there is some difference between them, not just names).
It depends on the species of rat snake you're breeding them with. My specialty would be North American rat snakes. I love just about anything in the Pantherophis genus. The Pantherophis genus includes things like corn snakes, everglades rat snakes, black rat snakes, gray rat snakes, emory rats, texas rats, yellow rats, rusty rats and bubblegum rats.
Outside of the Pantherophis genus(which used to be called Elaphe, and was just changed.. about a year ago?), you also have several other species. Look through the boards here, and you'll see posts about mandarin rats, blue beauties, subocs, and a ton of different species. Now, I don't know how many of those can interbreed, but just about everything in the Pantherophis genus can interbreed.
In fact, some hybrids are fairly commonplace. Creamsicle corn snakes are a hybrid between corn snakes & emory rat snakes.