Amends the Internal Revenue Code to: (1) increase the expensing allowance for depreciable business property from $100,000 to $200,000; (2) make such allowance permanent; (3) increase to $800,000 the asset cost threshold for calculating reductions in such allowance; (4) allow an annual inflation adjustment to the expensing allowance and the threshold amount after 2007; and (5) allow a taxpayer to revoke an election to expense such business property without the prior consent of the Secretary of the Treasury.