The Pew Charitable Trust has for many years sponsored the Pew Internet & American Life Project. Researchers there have produced many fine reports that range from Internet usage trends (highlighting surprising demographic data), to details on what activities people are doing online.
If you are interested in gathering data on social trends, demographics, or connectivity this is a wonderful place to visit. Check out the piece on Networked Workers, it will give you a sense on why people are flocking to SaaS and Cloud based applications.
All the reports are free.