I've mentioned this before, but I want to really focus on this entrepreneurial dream of "The Perfect Idea".  I know a lot of people that think they may one day start their own companies but they're waiting to have a great idea to build the company around.  Here are some core beliefs that I have regarding this:

Very few cool tech start-ups were founded on a great business idea.  The great ideas like Google Adwords, social networking, etc. all evolved out of stupid (or at least misguided) ideas.  Why?  Because it's nearly impossible to have a good idea about something that you're not familiar with, and you can't get familiar with an industry without starting to work in it.

Even if you do have a once in a lifetime idea, you're going to botch the implementation if you're waiting to become and entrepreneur.  If you spend the first ten years after college working at a giant corporation and then you have a brilliant idea, you'll have to learn how start-up companies work as you're trying to execute the idea.  It would be a shame to waste such a brilliant business model on your practice round.

Even if there is a perfect idea out there, and even if you do think of it yourself, there are people out there already working in that industry.  They're building infrastructure, learning about the market, and gaining valuable experience.  Those people will almost always beat the people that are sitting around waiting for an idea.

Blogging offers a great example of this.  Sometimes I sit around for hours trying to figure out what to write about.  Eventually I give up and start working on an old idea that I'm not wild about (like this post, to be honest).  The second I start typing, I come up with tons of new topics.  In the time I've been writing this post, I added six new documents to my "drafts" folder with topics way more interesting than this one.  But if I hadn't started this post, I never would have thought of the new ideas.