It is a lot easier and quicker now to bring a new service from concept to launch. One of the biggest things helping this is the emergence of new practical web frameworks like Ruby on Rails . This allows single person or tiny teams to incredible things in very short time.
There are other similar frameworks where you could do similar things quickly, but really Rails is one of those economy changing tools that is and will cause a lot of turmoil in the world of web applications.
Productivity improvements are a big part of the push from the bottom. Skipping the need for scaling up in people makes it much easier to get off the ground. $100K is quite a lush sum if all you need is three people for a couple of months.