How much value, in USD, does M$100 in profits have?

I've noticed that although M$100 is theoretically worth less than a dollar, people are willing to put much more energy into winning it than that number would suggest. Maybe because they're trading for fun instead of finances, or maybe they want to win mana because that's how Manifold keeps score.

To resolve this, I will either devise an informal test to run, wait for one of you to do it for me, or resolve to the market probability at a random date and time in the week before the close date. Given that discretion, I will not be trading in this market.

See also:

Sep 22, 1:18pm: I've extended the close date by a week because I have my hands full working on a bot for the trading bot contest, so I want some extra time to figure out how to run an informal test on this. If this has been disruptive for anyone please let me know.

Sep 22, 3:39pm: For clarity, this question includes the additional M$100 assumed to be in your account, not just the raw leaderboard numbers themselves.