Final Fight 3 (Super Famicom): ¥823 (¥11,000 cart-only on Suruga-ya) I did not know there was a Final Fight 3. I did not know it went for over $100 at places in Japan. I don't even want to see what the NA release goes for.
Gomoku Narabe Renju (Famicom): ¥514 (¥330 cart-only, ¥1990 complete on Suruga-ya) I never heard of Gomoku before, but having studied computer science and a strong interest in game design make it super interesting to read about. I'm not sure how much enjoyment one could get out of playing a Famicom AI, though.