Without giving it much thought, my kneejerk reaction is Lillipup. First time I saw it on a fan website I went "Awww!" That is bias, though, because it resembles a Yorkshire Terrier or a Silky Terrier... both of which are breeds I'm a fan of. xD
Other ones that make the list for me are Skitty, Emolga, Cubchoo, and Sandshrew.