For more in depth rules, and the files for the cards, go here: http://www.bgdf.com/node/6883
This, as yet untitled, Stock Market Game is a deckbuilding card game, similar to Dominion. If you've played Dominion before, this should come easily. The key differences are 1) There is an extra deck full of wacky cards, called the Event deck, that players can get cards from and 2) The winner is the person with the most Money. In essence, all Money is Treasure-Victory.
So how do you play?
There are four types of cards: Money, Shares, Events, and Bankrupt cards. Put out all the Money piles (they're green), put out 10 of the available Shares piles (they're blue), put out the Event deck (lots of colors) face down. Give each player 8 $1 cards and 2 Milk Shares. The basic game mechanic is simply selling whatever Shares are in your hand, and then buying new Shares. However, you can sometimes play Shares (like Actions in Dominion) to get more effects, such as drawing more cards, getting more Money, and other things. But if you play a Share on a turn, you can't sell it that turn. Now there is also the Event deck, which has cards in it that can change prices of Shares, that can sit in front of to give you extra stuff each turn, that can do mean things to other players, and other things. If you manage to reduce a Share's price to $0, the pile goes bankrupt, and those can no longer be bought or sold or played. The Event deck contains illegal cards as well as legal cards, and you are encouraged to use both. The game ends either when the highest value Money pile is empty ($2K), or when any four Shares go bankrupt, or when only one player remains (a player is forced out of the game when enough legal action is taken against them for being naughty). Player with the most Money wins!
It's a bit more complicate than that, but if you're interested enough to find out those complications, head over to the blog I posted, and print out the cards and start playing! This game has only been played twice so far, so it could really use some playtesting. Thanks in advance!