Evan Williams' Ten Rules for Web Startups:

  1. Be Narrow
  2. Be Different
  3. Be Casual
  4. Be Picky
  5. Be User-Centric
  6. Be Self-Centred
  7. Be Greedy
  8. Be Tiny
  9. Be Agile
  10. Be Balanced
  11. Be Wary

Each is unpacked, read it. The list is from 2005 -- Ev's big success then was Blogger. Since then, his new thing is Twitter. Not bad!