A couple that stand out to me.
YSU 2012: I believe it was #1 vs #2 in the country, YSU was the only loss for the Bison the previous year during the first title run, it was homecoming IIRC, and they even picked the game on College Gameday that morning. I think most fans were still a little unsure of whether that team was a title contender but after a 48-7 beatdown on YSU that day I think quite a few, myself included, started making Frisco plans (back in those days you could still get good, and cheap, Frisco tickets in early October).
WIU 2015: WIU had a pretty good team that year, I think they made the playoffs at 6-5 due to their insanely tough schedule. I believe it was Easton Stick's 1st start in the Fargodome and they laid the wood on the Leathernecks to the tune of 59-7 or something like that. That was also Zach Vraa's famous "hug the defender" catch game.
EDIT: Gotta add that 2007 Central Michigan game in there too. Going in I remember thinking that they'd have a decent shot to win if they played well but a 44-14 beatdown like they gave them never even crossed my mind.
You could do a whole thread just with playoff games. There was the Georgia Southern 2011 semi, the entire 2013 playoffs, the entire 2017 playoffs until Frisco. Montana to open the 2015 playoffs.....
We're f#$%in spoiled rotten as fans.