I can't remember if I've suggested this game or not before. However, this is a slightly different version than the one I had an idea of before. So here goes anyway.
Played for: Up to $100,000 (That's not a typo)
The game is similar to Mystery Price. The contestant is presented with a grocery product, which costs 95¢ or less. The contestant must correctly bank enough "loose change" in order to cover the cost of the grocery item. If they do, they win $10,000 (not a typo).
In order to bank their "loose change", they are presented with a ball roll down ramp, similar to
this item here. The slots are numbered with amounts varying from 1¢-50¢, depending on how much banked change they have (they change every turn). If, it any point in the game, the contestant goes over 99¢ (i.e. gets $1 or more in change), the game is over and the contestant wins nothing. The contestant can take as many turns as he/she wants, as long as they don't go over 99¢, and can stop whenever they feel they have enough change to cover the grocery item. Should they decide to stop and have enough money to cover the item, they win $10,000; if not, they lose.
Here's where the $100,000 comes in. Should the contestant reach at least 95¢, they automatically win the $10,000, as they will know they have enough change to cover the grocery item. If they wish, they can then bet their $10,000 and keep playing. Should the contestant reach 99¢ exactly, they win the $100,000. Of course, if they go over 99¢ at any time, they lose their $10,000.
The roll-down gameplay is identical to an arcade game I remember as a child. It even played the Price is Right theme and used "Come on Down!" as its catchphrase. Of course, that was played for tickets and not money.