To quote someone else from a previous QotD:
The pictures above are from my WTB thread, but yeah.. the most obscure non-TCG item in my collection are defintely the (thankfully new/sealed..) female boxers of the Look Upon the Stars Pokémon Center product line, which features Seviper. 
I also think the designers knew what they were doing, placing the Machoke + Seviper and Milotic both in the center, haha. 
Greetz,
Quuador