Cheapskate is an informal term for somebody who doesn't like to spend money and is prepared to go to great lengths to avoid spending it.
Calling somebody a cheapskate is rarely meant as a compliment, which is a bit unfair because being a proper cheapskate demands loads of stamina and dedication. For instance, most people after a night out will get a cab to take them home, but a cheapskate will either spend half a night waiting for one of the elusive and mythical creatures known as night buses or just walk, alright: stagger all the way home.
Once upon a time, I was a promising young cheapskate myself – wearing hand-me-downs, cutting my own hair, cadging cigarettes, going to the cinema on Monday mornings – but then I went and sold my soul to Steve Jobs. You can call Mac users lots of things but 'cheapskates' isn't one of them.