If maps and menus are your thing, you could do worse than checking out Europa Universalis 4—something you can do this weekend for absolutely no money at all.
It's a Paradox grand strategy game, and so all but guaranteed to be unlearnable in a single weekend. Nevertheless, if you think you're up to the task, you can head here to download the Steam temporary trial version. If nothing else, you should have time to conquer a few of the smaller nations. If you like what you play, the base game is currently 75% off.
For current owners, new expansion opportunities arrive in the form of the now released El Dorado DLC. The add-on's focus is on Central and South America, and it also features a nation designer that'll let you custom create your own empire.
Here's a tiny trailer:
