Other prominent mechanics that incorporate (or freely enable) sacrifice include: Food, Clues, Treasures, Sagas, Unearth, Encore, Evoke, any other temporary tokens such as Faerie Artisans or Hostility, cards with Upkeep, Quests, Exploit, Casualty and now Bargain
Tutoring an Aura or Equipment and providing a Flying body (even if only on your turn) is a good deal for four mana
Interestingly, though, Impostor Syndrome as a card is more than just a meme
Loxi: A 7/5 with Reach is honestly a really nice body to be tied to a filtering/draw effect
SUDDEN DEATH: Sometimes both players win at the same time
Having said that, condition matters a lot, and cards that score highly according to professional graders like PSA, BGS, CGC or Beckett tend to grow in value the most