Hewlett-Packard and Tektronix, two companies for whom I have worked, were once garage-shop companies. Most companies start up that way and grow bigger as they reach their goals. The founders of companies care about their companies and the employees, the people who take over leadership after them do not care nearly as much. Under the founders of HP and TEK, there were no lay-offs. In tough times, they found alternate solutions to keep people they hired employed. Howard, Bill, and Dave all felt that if you cared enough to help their company succeed that they would return the favor and care for you when times got tough. This speaks highly of the environment in smaller companies that are growing. The smaller companies with whom I am familiar, also have far less overhead in terms of paperwork and meetings and far more emphasis on getting the work done. If you are familiar with the Scrum Methodology (), the philosophy of a good smaller company fits more closely with rapid quality software development. I am not saying that larger companies cannot also develop quality software, it just requires more hurdle jumping. As a side-note, look up Skunk Works for an example of a big company doing just this.
Back to your original question, doing something you love is far more important than working for a large corporation. When choosing a company, choose wisely. Look for a company with either good financing or a great idea than you feel you can substantially contribute to it being successful.
Big companies do not provide the stability they once did (). I was project-lead at Hewlett-Packard when I was asked to put together training for the product development to be shipped to India. A bit later I was a part of the HP Work Force Reduction and given six weeks to find work within the company. At the same time, the CEO put a seven week moratorium on internal hires.
The bottom line is to choose what you want to do, look for a good company who is doing that, and then hone your skills in that area and show the company how you can help them with their success. Good luck.