Updated: The prices have gone up! Amazon has a ton of board games for 60-85% off their retail prices. Best bets:
No longer available
Uno for $3.99 and Yahtzee, Twister, Chutes and Ladders, Connect 4, Clue Secrets and Spies, [6[Jenga Max for $4.99 each. As always, shipping is free if you spend $25 or are an Amazon Prime member. There's no sales tax (except (KS, KY, ND, NY, WA).