Makoto breaking down in tears on the school roof when she believes that she's screwed everything up and can do nothing to fix it.
Makoto's final Time Leap.
And again, when Chiaki reappears for a few brief seconds after just leaving Makoto sobbing her heart out and tells her he'll be waiting for her in the future. Makoto's response is a bright, if extremely tearful smile and a quiet, "I'll come running."
For those watching the DVD, the included music video for the song "Garnet" can be this, especially if watching and listening while reading the subtitles.
I'll burn the days that I spent with you into my heart
So that I'll be all right even if I don't remember them