I was watching a video on Google today that featured Will Wright demonstrating and talking about a new video game he's been developing called Spore. (Online rumors indicate it should be out this summer.)
At the end of the video, he had an interesting statement about creative perseverance.
All the games I've worked on I've always hit obstacles, usually trying to convince other people it's a good idea or sellable or whatever. When I look back on this idea, the biggest obstacle I truly had was making myself believe that we could build the game. My own imagination was the biggest bottleneck. Once I truly believed that this game was buildable, it proved to be actually quite easy to con, I mean to persuade the rest of my staff and the executives and everything that we could do it. So I'd encourage all of you, if you've got like some totally weird idea that is just so far outside the box that you think there's no way that would work, go back occasionally and revisit those ideas because you just never know where they might lead to.