Something I just thought of three days ago, and haven't worked on yet.
A game for 3 to 6 players about collecting comic books, played over 9 rounds. Each round, copies of the latest issues for several comics arrive at the comics store. The issues are good or bad objectively (i.e. they receive a hidden objective rating). The past issues still in the store drop in price. The previous past issues are sent to the used bookstore. At the used bookstore, the ratings of issues are known, and the prices are determined by a) how many of the previous issues have sold, b) whether the issues were good, and c) whether the comic series is good or bad, on the whole.
When someone buys an issue from the comic store (where the rating is still hidden), he or she gives the issue a personal rating. If someone else buys the issue based on their recommendation, and the issue's rating is, in fact, good, they gain Cred. If they mis-represent an issue's value, they lose Cred.
The game starts with asking your parents for money. This amount is limited until you've paid back all the money, after which the amount you can borrow increases. Repeat, with the amount increasing each time.
There is a trading phase.
There is a phase of selling to, and buying from, the used bookstore.
At game's end, you gain Cred or cash for your collection. There are two winners: the player with the most Cred is the Cred winner. The player with the most money is the cash winner.