Though President Obama expressed confidence late Wednesday night that a government shutdown would be avoided, federal departments and others across the country are preparing for the worst.

After a meeting with House Speaker John Boehner and Senate Majority Leader Harry Reid at the White House, Obama said it would be "inexcusable" not to reach a deal and expects lawmakers from both parties to work through the night to reach a deal.

Late Monday night the White House Office of Management and Budget told the leaders of federal agencies "to share contingency plans with senior managers."

"In any shutdown, the government does not completely cease functioning, of course. Activities that are essential to national security, like military operations, can continue. Air traffic control and other public safety functions are exempt from shutdowns. Federal prisons still operate; law enforcement and criminal investigations can continue. Employees deemed essential to the functioning of government can come to work," reports the New York Times.

But with 48 hours to go before the government shutdown deadline of midnight on Friday, federal agencies and others are laying out plans for dealing with a shutdown.

So what does a government shutdown mean?

• Furloughs for about 800,000 (of 1.9 million) federal employees nationwide
• Suspension of payments for uniformed military members--even those engaged in combat
• Freeze the processing of IRS paper returns. "Only 30% of tax filings are done the old-fashioned way via paper, but those returns would be set aside, and any refunds for those filings would be delayed," the L.A. Times reports.
• No Blackberrys for "nonessential employees," says the chairman of the Committee on House Administration
• National parks would be shut down. USA Today notes, "All 393 national parks would close, as would other federal tourist attractions such as the Smithsonian Institution. Washington's annual Cherry Blossom Festival — with its signature event, Saturday's Cherry Blossom Parade — would be cancelled."
• The New York Times looks at the affects on the postal service (none) and food stamps (likely unaffected for April), among others. "If a shutdown occurs, the Federal Housing Administration, the world’s largest insurer of mortgages, could not make new loan guarantees for homebuyers," the Times reports.
• The L.A. Times has a list of 13 ways a shutdown would affect the nation including: "About half a million visitors to the National Zoo and the major Smithsonian museums on the Mall would be turned away this weekend alone" and "The Environmental Protection Agency would  stop safeguarding the health and the environment of millions of Americans."
• In addition to a shutdown countdown, National Journal takes a look at what was shut down in 1995 and what could be shut down again. Two examples: visa and passport services--"Some passport agencies shut down altogether while others operated with minimal staff. Thousands of visa and passport applications went unprocessed" and health services--"New patients were not accepted into clinical research trials at the National Institutes of Health, and the Centers for Disease Control and Prevention stopped disease surveillance."

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