This bot was created based on this tutorial http://sscaitournament.com/index.php?action=tutorial and is capable of winning against very basic bots or computer
It creates as much marines as possible, sending them to nearest choke point. When it has 50 of more of them, it attack at last remembered building.
I spent only ~ 5 hours from scratch to publish this bot to http://sscaitournament.com/ and then fix him a little. It is indeed very simple and very stupid bot, but at least it is utilizing minerals properly.
Licence - do whatever you want with this code :), I put MIT licence to make it official