I like your second tip best. The first one won't work if (like me) you rarely use cash. The third won't work and the fourth isn't needed if you're fairly vigilant about your money. And the fifth only works on limited catgeories and opportunities.

Here's one I use all the time - take all your credit card rewards in cash and deposit them into an account other than your main checking account. Then, invest them and/or use them to pay for gifts and vacations.