2006 was maybe the best game ever in my lifetime between the 2 teams just because the stakes were so high.....but my all time favorite may have been 2004. OSU entered as an underdog and on a losing streak. The series under Tressel was in our favor, 2-1, but I believe that was the coming out party for the aforementioned class of 2006. Just a breakout game full of big plays for Ohio St.
2005 may have been the most exciting game between the 2 rivals in that span, though.