It turns out you can make too much cash in Grand Theft Auto V. As user OmegaDL50 discovered and posted via NeoGaf, once a player steals, assassinates and sells enough hitchhikers to garner $2,147,483,647 players will find that their cash will roll over into a negative value.
The glitch is due to how GTA V deals with cash, as a 32-bit integer, but what's important here is to use some of that dough! It's fairly easy to get this much cash in Grand Theft Auto V if you invest in the stock market and carry out some assassination missions.
Until this glitch get's cleared up, be sure to buy some stuff and don't be such a hoarder. Remember: you can't take your cash to GTA V Online so hone your skills and save your energy for GTA V Online launches on October 1.