Exxon has already paid $19.828 billion in income taxes for 2008 (

data here

), and will probably pay almost $40 billion in income taxes this year (see graph above, income tax data for 1999-2007 taken from Exxon's annual reports).

To put $40 billion of income taxes in perspective, it can be reasonably estimated that Exxon will pay more in income taxes this year (both here and outside the U.S.) than the entire bottom 50% of American individual taxpayers (about 67 million) will pay in income taxes this year.

Using IRS tax data through 2005 (in Table 6,

data here

), and making reasonable projections for tax payments in 2006, 2007 and 2008, the bottom 50% of taxpayers will pay an estimated $34 billion in income taxes this year, and it will probably be the first time in U.S. history that a single corporation paid more in income taxes than the entire bottom 50% of U.S. taxpayers.

Update 1: Of course, corporations don't actually pay taxes, they collect them, in the form of higher prices for consumers, lower wages for employees and/or lower dividends for shareholders. In other words, people pay all taxes in their roles as consumers, workers and shareholders.