I don't agree with this "Three Strikes and your Company is Out!" advice. A company asked me to take a paycheck late once (basically giving us a form that said we can stay and get paid late or we can quit and get our last check late), and I agreed, especially after the client apologized personally and said he'd wire the money as soon as it got freed up. I got two paychecks like a week and a half later.

A month later the form got passed out again. That second time I really, really considered, on principle, going with "quit", even though I didn't have anything else lined up. Before I made the decision, though, I was called in to the office and laid off, along with about half of the staff. And then I got that check about two weeks later.

That first time is a harbinger of things to come. Don't ignore it. Start looking for something else immediately. You might not get a second warning.