I've recently left my job to do (solo) consulting full time. I've found that there are a number of recurring legal and administrative tasks that I, as a business owner, need to stay on top of.
Tasks such as invoicing clients by specific dates (varies per client), filing taxes (federal estimated income, unemployment, business taxes, et al), paying the business AMEX card, renewing professional insurance and licenses, renewing certifications, paying subcontractors, filing an annual report with the secretary of state, and so on.
How are other businesses handling these tasks? A shared Outlook calendar, specialized software, something else? How effective are these solutions?