Early Retirement Plus Working?

In this economy I need to make a decision in the next few days whether or not to apply early for Social Security benefits in the USA.  I do not reach full retirement age for 2.5 years, so I would have a smaller benefit amount each month.  The benefits would be recalculated when I reach retirement age and, if I keep working on jobs that pay into social security (as opposed to teaching jobs in IL and to other jobs that do not pay social security) I could end up with a bigger benefit than if I just wait until later.  The difference between what I would earn at full retirement age and what I would earn now is about $300 per month--significant for a long-term view.

At the same time, while I am actively working three businesses and pursuing clients and customers, having a steady flow of income while I build more business--or take-on some contract or other part-time work--would do wonders for my "security" and sense of well being.

It takes a month for the process to start, so, if I plan to do something soon, I will need to act in the next day or so.  I will then have to make estimated tax payments for social security income, so I'll be back to Quicken before I know it.