I would for sure go with Leopard Geckos, you could get a very impressive breeding colony going in a 90G enclosure. I keep a 55G Leopard Gecko enclosure in my living room, currently it only houses one gecko but just last night while watching TV she was out and about, Like a neon light running around the enclosure. I get nothing but compliments even from people that don't like reptiles.
Foot Hill Reptiles