Personally, I don't understand why the IRS doesn't give me a way to electronically submit my taxes to them directly. I hate having to use a third party.
States have their own programs (e.g. New York http://www.tax.ny.gov/pit/efile/pit_webfile.htm )
http://www.irs.gov/pub/irs-utl/Free_Online_Electronic_Tax_Fi...
Under Summary: "During the term of this Agreement, the IRS will not compete with the Consortium in providing free, online tax return preparation and filing services to taxpayers."