I have been fortunate enough to have found an additional niche area that has made me even more valuable. You can do this by finding a high demand area that requires your skills and honing your skill proficiency to suit that market. My chosen market is Microsoft Dynamics CRM but it could doing .NET development as it applies to SharePoint or any other high demand field that utilizes .NET development.
Even, if you know nothing there is hope. I could hire five .NET people today and many more when we sell our next gig but we can't honestly find enough good people. Download Visual Studio Express and go through the tutorial videos linked below.
My recommendation would be to start from scratch (the videos above) and then work your way into a .NET certification program. The tests are $150 a piece. As an example, in the Twin Cities you can expect to earn close to 40-50k as an entry level .NET developer. Honestly, within five years you should be able to work your way into 90k. Even more exciting is the fact that they have clamped down on H1-B visas which has boosted the price. In the Washington DC area there is plenty of jobs (for qualified individuals) to make over 140k in .NET dev for CRM. I have seen the values for these people go up rapidly in recent years and that trend does not seem to be slowing at all.
-I hope this helps!