QuickTime Movie Player

Sparkle

MPEG Movie Player (A bit dated, since QuickTime 3.0 now supports MPEG)

Video for Windows

Microsoft's QuickTime-to-AVI-to-QuickTime conversion tools

MacAnim

FLI, DL, & GL Player

MovieConversion

Converts between PICT, PICS, and QuickTime formats (A Hypercard stack)

QuickTime VR Player