FREE Postage-Paid Spongebob Squarepants Postcard At Your Local Post Office! Posted on December 6, 2013 by Cathy Go to your local post office between now and January 4 to get a FREE Spongebob Squarepants Postcard, no stamp needed! Get more details HERE, and while you’re there, your child can make their own custom stationery to print out. Want more free stuff? Check out our Freebie forum!