Obviously, Spock's death scene with Kirk on the other side of the plexiglass is up there.
Geordi seeing the sunrise in Insurrection.
Data being reunited with Spot.
Geordi forgiving Data for panicking (thereby letting Soran kidnap and torture Geordi).
Data calling to Picard as the crew abandons the Enterprise-E, and Picard's subsequent conversation with Lily.
George Kirk's last conversation with his wife as they name their newborn son.
Kirk destroying the Enterprise and then watching it's wreck crashing through the sky; his conversation with McCoy about "turning death in to a fighting chance to live."
Kirk's final log entry at the end of Star Trek VI.
Chekov telling Kirk and Spock that the "nuclear wessel" is the Enterprise (aircraft carrier).
McCoy reliving euthanizing his father