Competition between coca-cola and pepsi is a real life example of game theory. Each of them can decide to sell the products at normal price or discount price. The dominant strategy of eah firm is discount, and Nash equilibrium is discount|discount.
The game I have played from UBC is TCP backoff game. The dealy time I and my collegue get according to our choice of TCP protocol is as follows:
Here, the dominant strategy for each is using a defective protocol, and Nash equilibrium is defective|defective.