Swampert, Quagsire, Gastrodon, Camerupt, Trapinch/Vibrava/Flygon, Torterra and Swinub/Piloswine. Yep, it's a tie between quite many Ground types, but they're all cute in their own way so I couldn't decide which one I like best. :3
*edit* I also like Hippopotas, Onix and Steelix. o.o