Check your car.
Never go on a last minute travel by land without having your car checked. Don't leave anything to chance. So maybe the next gas station/repair shop is just 10 miles away. What if your car breaks down – are you willing to walk/hitch the rest of the way just to get your car checked? Make sure everything is in order before you even leave your driveway.
Stop and get your bearings.
Last minute trips can be forever trips if you get lost. If you've been traveling a while on the road, stop and try to see if you're going in the right direction or at least taking the right road. Use landmarks and street signs to determine your exact location. Got a GPRS? Use it.
Going public? Confirm your tickets.
If you'll be taking your last minute travel by land on a public transportation, make sure to get your tickets ahead of time. You could queue, of course but if you want to make sure you travel faster, have your tickets on hand.
Have cash on hand.
Not every destination you arrive at might have an ATM or a bank. In case you need cash fast, at least you have something in your wallet, bag or pocket. If you're traveling by land at the last minute, make sure you have cash in change -- $1, $5, $10 and $20 bills, along with loose change in coins. So in case you find a hotel, inn or restaurant that will only take cash, you're ready.
Plus, you never know if you'll have to make a call from a telephone booth. After all, there are still areas where mobile phones won't work.