Start with small experiments that solve real problems that people are having. See what works and build on that.
This is the opposite of "Get Big or Get Out." One of the benefits of the web is that it's possible to make smaller companies that solve specific problems without costing a fortune in startup costs. Especially with technologies like Google App Engine and the like, it's becoming easier and easier to create full-powered, scaleable systems from dorm rooms and garages.
The companies that win will be the most fun places to work.
Contrary to popular belief, technology is neither the problem nor the solution. Technology is never a measure of itself and always a measure of us. (This has always been the best evaluator for science-fiction stories).
Leaders tend to form shells around themselves, for protection from being overwhelmed. But then the leader cannot grow outside the border of the shell. And, cut off from new energy, what's inside begins to shrivel and die.
Your strengths, the things that make your business successful, are the very things that will become weaknesses and bring you down.
Bruce Eckel (www.BruceEckel.com) provides development assistance in Python with user interfaces in Flex. He is the author of Thinking in Java (Prentice-Hall, 1998, 2nd Edition, 2000, 3rd Edition, 2003, 4th Edition, 2005), the Hands-On Java Seminar CD ROM (available on the Web site), Thinking in C++ (PH 1995; 2nd edition 2000, Volume 2 with Chuck Allison, 2003), C++ Inside & Out (Osborne/McGraw-Hill 1993), among others. He's given hundreds of presentations throughout the world, published over 150 articles in numerous magazines, was a founding member of the ANSI/ISO C++ committee and speaks regularly at conferences.