How to save money as a start-up

Obviously as a start-up finance is at a premium so saving money is just as important as earning it.  There's an interesting piece here on Mint about ways you can do that.

1. Break each customer down into its own profit and loss statement so you can discover your most profitable customers and focus on them
2. Generate financial reports on a monthly basis
3. Raise money as late as possible so you have the opportunity to explore all other options first
4. Your first few hires should work on the fumes of your dream rather than a salary
5. Keep your fixed overheads low
6. Make sure you have money available when you don't need it rather than scrabbling around desperately when you do
7. Focus on profit rather than revenue
8. Sign your own cheques
9. Barter
10. Have your customers finance your business

What do you think of the tips?  Have you used any of them yourself?  Any others to add?