I think after some thought about it, it's Mathews' OT winner against the Jets, in a game that the refs I felt tried to win for the Jets, we didn't get that obvious slash call in OT (broke the stick of Marner I believe) and then Rielly delivers that beaut saucer pass, and Matthews finishes with a filthy backhand to win it. Against the the team that's probably #2 in the division when all is said and done.
Felt like an "against all odds" moment at the time, and was the memorable.
Also remember the Edmonton dominating sweep, for sure.
Also, Spezza's hattrick was also memorable for me, against the 'Nucks.
On the negative side, I do remember Ottawa's 5 goal comeback as well.