I find it a helpful exercise to examine federal budget statistics in terms of dollars per capita. The raw numbers are just too big for our intuition to handle well. For historical context, the correct unit of measurement is usually GDP. However, if we're just looking at the present, I find dollars per capita gives me a more visceral understanding of how much money is involved.

Allow me to illustrate. The following quantities are given in dollars per U.S. resident.

Federal govt. outlays for FY 2007
total	9200
discretionary: defense	1740
discretionary: nondefense	1680
Social Security	1930
Medicare	1570
welfare programs	1240
other mandatory spending	542
undistributed offseting receipts	-313
net interest payments	822

The estimated savings due to proposed cuts and reforms in Bush's 2007 budget is $68 per U.S. resident.

The data sources for my calculations are the White House (p. 7), the OMB (p. 133, 292), and the Census Bureau. (I used simple linear interpolation for my population estimate, so I only trust my results out to three significant figures, and have displayed them accordingly. Of course, my data sources are themselves estimates; I don't know to how many significant figures they should be trusted.)