When my dad was playing about a week ago, he managed to hit the money cap. So, not really a glitch, but there's a number overflow when you hit 2 trillion dollars. He was playing on version 0.0.731.
When he sold the weapon that brought him over 2 trillion, his money went negative, so he had negative 2 trillion.
Maybe add a limit, or find some way to keep it from overflowing?