Power Grid is the updated release of the Friedemann Friese crayon game Funkenschlag. It removes the crayon aspect from network building in the original edition, while retaining the fluctuating commodities market like McMulti and an auction round intensity reminiscent of The Princes of Florence.
The object of Power Grid is to supply the most cities with power when someone's network gains a predetermined size. In this new edition, players mark pre-existing routes between cities for connection, and then bid against each other to purchase the power plants that they use to power their cities.
However, as plants are purchased, newer, more efficient plants become available, so by merely purchasing, you're potentially allowing others access to superior equipment.
Additionally, players must acquire the raw materials (coal, oil, garbage, and uranium) needed to power said plants (except for the 'renewable' windfarm/ solar plants, which require no fuel), making it a constant struggle to upgrade your plants for maximum efficiency while still retaining enough wealth to quickly expand your network to get the cheapest routes.
Power Grid has players trying to power the most cities. Power plants are auctioned off each turn, and each power plant consumes some number of some type of resource to power some number of cities. Players buy power plants, "build" into cities, buy resources, and gain an income determined by the number of cities they power. The first person to "build" into at least 14 cities triggers the end game, the winner being the person who powered the most cities (money being a tie breaker).
This game has an interesting negative feedback loop: the player in the lead acts first at auctioning off a power plant (usually the worst position), and acts last at building into cities and buying resources. Resources have a sliding price, so the more that are purchased the more expensive they get. Great depth of strategy, especially in balancing your income as money is only a tie-breaker.