There are lots of ways to get inspired but I found myself always going back and watching this video when I need a little kick in the ass.
This is an awesome talk from David Heinemeier Hansson, creator of the Ruby on Rails framework and Partner at 37Signals that gives insight into creating a profitable startup company.
http://www.youtube.com/watch?v=0CDXJ6bMkMY&w=640&h=385