Basically what happens is there is 3 companies (soon to be more) to invest in each company is given chances of making or losing money based on the real stock (if its up its a greater chance of making mony if its down theres a greater chance of losing money) you insert gold (however much you want) through the first slot and you receive either sticks (which represent a loss) or gold! you can get 2 gold 1 gold or 2 sticks so you either double your money, break even or lose it all. there are a few flaws such as the fact that sticks may trigger the system giving you free money but im trying to find a way around it here are some pics, the redstone is insanely simple to make as well.
so it's basically a 3 chance slot machine? this would be more useful if/when we get the hopper/trapped chests (gold flows into hopper above trapped chest, chest sends out redstone signal, and then it hits the dispensers, allowing for a refill of the dispensers in survival). (now for a slightly off-topic tangent) It's a interesting design, and probably with a little tweaking, you could turn it into a "full" slot machine... then you just need a roulette table, a black jack table, and a poker table, and you could open up your very own "Villager Casino".
Haha well thankyou and coincidently I do have a casino with a different type of slot machine the entire time I was making this I knew the slots would be brought up but hey stocks are a gamble aren't they