Here is another list of 17 Pithy Insights For Startup Founders. The ones I liked the most are
6. Eventually, your product will need to work and do something useful. No amount of marketing or strategy will get you around this.
11. Force yourself to write, as it will force you to think.
(blogging, wiki, email, IM, anything). And, of course,
13. The problem you solve should be ugly. The solution you build should be beautiful.
And this one
14. Even the most successful startup ideas had 100 reasons not to pursue them. There is no perfect idea.
which goes really well with that thing I just posted.