Season 2 with Dru and Spike when it seems that they're going to kiss but instead they merely touch foreheads and turn to face the camera in perfect unison.
The fight scene between Xander and Harmony in Season 4 leaves me rolling on the floor ever time I see it.
The Gentlemen floating along the campus while their straight-jacketed henchmen gambol around them
Willow and Oz in the van when he is leaving her (the last time)
The slow-mo sequence in Season 3 when Faith realizes that she's been played by Angel & Buffy and that he was never really evil
When Buffy turns around at the prom and sees Angel in his tux coming toward her (same ep: when Buffy is crying with Willow and feeling as if she cannot breathe...)
