If you've got Washington vacation plans

The shutdown has closed the National Archives in Washington.
You may want to rethink them. Many D.C. tourists sites — including the National Archives (home to the original Declaration of Independence and U.S. Constitution), Ford's Theatre and the White House Visitor Center — are closed.
The Smithsonian says its many museums and the National Zoo will close starting on Jan. 2.
If you work for the government

Tens of thousands of federal workers will be furloughed.
You could find yourself sitting at home with Judge Judy but without pay. About 40% of the civilian federal workforce is considered "nonessential" during a shutdown and is put on furlough. Up to 850,000 workers were furloughed in 2013.
Usually, federal employees who stay home receive back pay after the shutdown ends. But the delayed paychecks can throw off family budgets.
If you're planning a trip to a national park

During previous shutdowns, America's parks turned away visitors and campers.
You'll need to do some research. The National Park Service website warns: "Some national parks may remain accessible to visitors; however, access may change without notice. Some parks are closed completely."
States have rushed in with funding to keep some parks operating as normal, though visitor centers at many parks are closed and services are limited. Bathrooms may be closed — or, if they're open, you won't find any t.p.
To see what's open, your best bet is to check the web page for the specific park you're interested in visiting.
If you worry about bad guys seeing an opening

TSA agents will remain on the job.
Fear not: The FBI, the Coast Guard, the U.S. Border Patrol, food inspectors and federal prison guards are all in the "essential" part of government that stays open during a shutdown.
The TSA will keep scanning you and doing those pat-downs at the airport, and America's military will remain on duty around the world.
But the troops may not be paid.
If you get money from Uncle Sam

The government pays out Social Security and other benefits during a shutdown.
Though Social Security payments do continue going out during a shutdown, you'll be out of luck if you lose your Social Security card. You may have a long wait for a replacement.
Medicare and Medicaid benefits are still being paid.
If you've got important snail mail coming

Mail service will keep going if the government shuts down.
No need to worry about getting your mail, because you can include shutdowns with those things that don't stop the U.S. Postal Service — like snow, rain and "gloom of night."
The money for the post office doesn't get tied up in these shutdown brawls, so your non-electronic bills and all of those Bed Bath & Beyond coupons will keep coming.