Well, on little old Yahoo Messenger, I and a few fellow game show geeks have a slightly altered version of Sale of the Century. Allow me to spell out the changes...as few as they may be, for your opinions.
Extended Speed Round - This is largely because people have to type answers and not use voice for answers due to tech issues...but the speed round is billed as, fittingly, The Century Round with 100 seconds on the clock.
The End Game is vaguely like shopping but goes differently. Hopefully you can follow this, as I tend to overexplain.
While the main game is played for money, the money has a different effect.
No matter what game total the winner has, he or she in essence plays for a designated endgame prize. Day 1 - The first prize in a lot, Day 2 a more expensive prize in the lot, etc. Day 5 - They get the car, if they so choose to leave, Day 6- The Lot, Day 7 - The escalating cash Jackpot (we go with $50,000 + $2,000 for every day it's not won) and the lot.
Where does the money come in, then? Ahhh, it becomes an extra temptation angle. Each day also is worth money. A certain multiplier for each day. It's your total main game score times the following multipliers in the following circumstances:
Day 1 - 5
Day 2 - 10
Day 3 - 15
Day 4 - 20
Day 5 - 25
Day 6 - 50
Day 7 - 100
A person could be tempted when they've amassed a high enough cumulative game total and a 20 or 25X multiplier to go with the cash, and the designated prize. It adds temptation.
Example: Alright, day 5...you've amassed main game cash and prizes totalling $12,500. You also have been fairly good to get this far and have amassed $475 Sale dollars in the main game. And, because it's day 5, you get this lovely (insert mid-high level car or SUV here) worth $33,000. Let's do the math...you can leave with not just $45,500 in game cash and prizes, but an additional 25 times your $525 Sale dollars, or $13,125. You could leave us right here and now with $58,625 in cash, car, and prizes...or you could risk it for the lot of prizes and a whole lot more money.
EDIT: In the end, for it to have its best effect, the multipliers might be tweaked to say 10, 20, 30, 40, 50, 100, 200 or something to that effect, but it could also be created by making the main game +10/-10 in lieu of +5/-5.