The government might shut down on April 8th, if congress can't come up with a new budget. Not all services will be affected. Here are some things that will NOT be affected.
Need to send a letter to grandma? Ordering something off eBay? You'll still be able to get your mail during a governmental shutdown, and you won't have to ship via FedEx or UPS. The mail has a separate budget and will still keep on running.
If you depend on Medicare for your health care, you'll be okay during a governmental shut down. If you're trying to apply for Medicare or Medicaid, you may have difficulty; however, since these programs are administered in part by the state, you still might be able to apply.
Grandma and grandpa will continue to be paid throughout the government shutdown, but if you're getting ready to retire, you might want to consider working for a little while longer, as new applications might not be taken.
Essential services will not be shut down. The airports and borders will still be guarded, and prison guards will also still continue to work. Federal museums and National Parks, on the other hand, are not essential, and will be shut down.
The poorest people in our country won't starve, as food stamps will continue to go out (the shutdown may affect new people applying though). Military pay will be postponed (they will get paid, but won't see their checks until the budget agreement is reached). If you know somebody in the military and the budget standoff goes on too long, you may want to help out your fellow soldiers with food and other necessities.
select one here...