For those of us who are not privileged enough to go regularly, it's often a matter of luck - hoping that the games you can attend turn out to be classics. That has its charm too. Looking at the ones I happened to attend (which included many miserable and so-so ones - the recent game against Milan at home, my oldest son's first home game this season against Wolves, Nuno's last or penultimate game at Vitesse in the Conference League last year, Ghent-away in 2017, incidentally the only game in the Poch era I went to, and the 1-6 defeat at home to Chelsea with my dad in, what, 1997?), I have not been particularly lucky. The only NLD I ever attended (the Ziege free-kick) was memorable too, but I would name these as my 'greatest' five:
Spurs - Leicester 1-0 (LC final 1999, for obvious reasons - I remember singing "we only had ten men" with thousands of others on the train back to Central London).
Spurs - Kaiserslautern 1-0 (lots of rain under the lights, a glorious Ginola performance and an Iversen penalty goal that I thought would not be enough to go through - turned out to be correct).
Spurs - Southampton 7-2 (a season when I lived in London and attended almost every home game. Turned out to be a really crap season though with the Iversen-Armstrong combo, but this one was unexpected).
Spurs - Everton 3-2 (2000, because Rebrov scored twice and hit the bar and I thought it would be the making of him and that we had turned a corner).
PSV - Spurs 0-1 (2007? Great night, Berbatov was unstoppable ... but going out on penalties killed the joy).