probably already posted but too lazy to scroll through the endless Rand-bot babble that is so common in political threads here. This is why saying "stimulate the economy by cutting corporate taxes" is just moronic.
ROI for each dollar allocated to tax cuts or spending increases. According to a top Republican economist and advisor to John McCain:
http://www.economy.com/mark-zandi/documents/Economic_Stimulus_House_Plan_012109.pdf
Table 2: Fiscal Stimulus Bang for the Buck
Source: Moody's Economy.com
Bang for the Buck
Tax Cuts
Non-refundable Lump-Sum Tax Rebate 1.01
Refundable Lump-Sum Tax Rebate 1.22
Temporary Tax Cuts
Payroll Tax Holiday 1.28
Across the Board Tax Cut 1.03
Accelerated Depreciation 0.25
Permanent Tax Cuts
Extend Alternative Minimum Tax Patch 0.49
Make Bush Income Tax Cuts Permanent 0.31
Make Dividend and Capital Gains Tax Cuts Permanent 0.38
Cut in Corporate Tax Rate 0.30
Spending Increases
Extending Unemployment Insurance Benefits 1.63
Temporary Increase in Food Stamps 1.73
General Aid to State Governments 1.38
Increased Infrastructure Spending 1.59
Note: The bang for the buck is estimated by the one year $ change in GDP for a given $ reduction in federal tax revenue or increase in spending