I remember seeing somewhere an opening line, where one side gets rook and the other one 5 pawns, it was pretty sharp. I also remember that it's now considered dubious, because one of the sides was proven to be much better. Unfortunately I don't remember which side was which and also the parent opening or the starting moves. Does this line come to mind to someone? It would be greatly appreciated.
Is it this line in the Advance Caro-Kann of which you are thinking?
[FEN ""] 1. e4 c6 2. d4 d5 3. e5 Bf5 4. Nc3 e6 5. g4 Bg6 6. Nge2 c5 7. h4 cxd4 8. Nxd4 h5 9. f4 hxg4 10. Bb5+ Nd7 11. f5 Rxh4 12. Rf1 exf5 13. e6 fxe6 14. Nxe6 Qe7 15. Qe2 Rh2 16. Nc7+ Kd8 17. Qxe7+ Bxe7 18. Bf4 Rxc2 19. Nxa8 Bh4+ 20. Kd1 Rxb2