In the time before DVR, TiVo, OnDemand, and Hulu, you had to be there or have a good programmable VCR.
  1. Thursday night on NBC: Must See TV, Friends era
  2. Sunday night on ABC: The Magical World of Disney, 1980s
  3. Monday night on the CW: Buffy the Vampire Slayer era
  4. Thursday Night, also NBC, The Office era
    Suggested by @Boogie
  5. TGIF
    Suggested by @jmewants2travel