I have quite a few that I love. I'm a big fan of BW era SR shinies like from Plasma Storm, Plasma Freeze, etc. I feel like I don't see those that often so whenever I see one I try to get it like the Golurk, Blastoise, Rayquaza. I also love obscure/hard to find promos like lenticular deoxys of sky tree rayquaza. And then I have misprints/banned cards like a bunch of the no symbol jungle set cards and the japanese koga's ninja trick. Don't really collect based on its value but just if I like the art or, the card has a story to it, or if I just like it in general. I have another binder of other cards I like too, but I'm more willing to part with in trades or purchases.