i have owned a number of lizard and snake species. The most interesting i think are chameleons . If you are considering a larger species, Savanah monitors are nice. they are more docile then most monitor species. Or a blue tongue skink. i have a western hognose snake right now, by far the most interesting snake i've ever owned. They display a hood like a cobra. and if you really piss them off they will play dead. King snakes and rat snakes are great for beginners. King snakes are cannibals though so you can't put them with other snakes.