I think there's a logical flaw in asking for such a script - anyone who knows how to do it will either have already done it and kept quiet or considered it and decied not to do it.
That said I'd be happy to write such a script for large sums of ISK BUT I don't know how to make money off the market or what such a script would do.
There's also a logical flaw in making a market script for isk, in that if it's any good you could make large sums of isk yourself.
There's several methods by which you could make a bot that plays the market to make isk. The simplest would be one that finds low sell orders and high buy orders for an item (likely between regions), and simply buys, moves, and sells the item. I haven't made one like that myself, but its probably comparable to mining in income.
A bit more complex one looks for items that have a wide margin between current buy/sell orders, and places orders of its own to compete with those. This works best at a trade hub, which also has the advantage of not having to move the items. I made a fairly basic script which did this with high-volume low-cost items in Jita (ammo, implants, several modules), and it didn't do too bad.
What I had started on before I stopped playing EVE, was a script that would attempt to track orders as they filled, and doing so be able to get information like you find on the market history screen (units sold/bought, price), but for the individual stations that the orders were at, rather than region-wide. This would allow you to place buy orders that had a history of low prices (obviously taking current competition into account), and then move those items where they historically sold well, and put them up in a sell order. I had the tracking of orders as they were filled part working pretty well, but never finished the rest of it so I don't know exactly how well this method would work compared to a better script than mine that just sits at a trade hub.
Hopefully this gives you some ideas!
tl;dr: Buy low, sell high.
- connection doesn't work) to apply more hard logic - spread evaluation and the such