Yes, according to the all-knowing Jedi Master of the regionals, there's an abundance of hotel rooms around Newark for $50.

However, if you don't want your kidneys cut out of you while you sleep, there are some hotels with deals. It depends on who you're with, but I think the Marriott right on the field has rooms for $80 and the Renaissance on 1 and 9 has rooms for $69. Both are excellent and I've stayed at both.