Pretty much depends on what your interested to work with. Whats your budget? How many space & time do you have to devote to your pet? One good pet (and i think pretty much people agree on this) is the leopard gecko (Eublepharis macularius). Others include :
Snakes > feeding bout once a week, depending size, age, & species sex (if its pregnant), not for the squirmish : Ball pythons, african brown house snakes, corn snakes
Lizards > feeding bout every other day, varies depending on age, size, and species sex (if its pregnant) : Besides leopards, blue tongues (if you are ready to devote more space and money), bearded dragons
Turts & torts > kinda messy (especially aquatic turtles), need bigs enclosures, but are quick to recognize their keepers (and personally, i think they're totaly cute too ^^) : RES (Red Eared Sliders), box turts, some tortoises (the turt forum can help ^^)
Amphibians > i'm no expert, but fairly small enclosures, feeding same as lizards, some are realy2 tiny, meaning smalles food items. consider them more of a display animal : Whites tree frog, Axolotl's, japanese fire bellied newts, oriental fire belly toads (careful, some amphibians are poisonous)
For all, i recomend CB (captive bred) animals, wich adjust better to captivity. Never forget to quarantine any new animal vet checks (make sure the vet is expirienced with reptiles), vitamin mineral supplements, especialy for insectivores and herbivores. For more info, there are some care guide books on the market. Good luck with your choice
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My "babies" :
1.0.0 Indo BTS (Tiliqua gigas gigas)
0.0.1 Rainbow skinks (Mabuya multifasciata)
1.0.2 RES (Trachemys scripta elegans)
0.0.3 Amboina box turtles (Cuora amboinensis)
1.0.0 Chinese softshell (Trionyx sinensis)
1.0.0 Asian leaf turtle (Cyclemys dentata)
1.0.0 Leopard gecko (Eublepharis macularius)
And still growing...