alot of games have number caps including runescape. Have you ever noticed something being capped at 65535? thats cause its 2 to the 16. likewise, 2 to the 32 is 17,179,869,184. Therefore i would have thought the cap would be 17 billion, it being a 32 bit system. Caps are there to prevent negativity. In some old tycoon games, if you tried to construct something stupidly expensively, the cost would go so high, it would be negative and actually give you money rather than take it away. The same goes for Runescape. Plus, if you had 2.1 billion, you could always splash out on something pointless like 100 phats to lower that a bit.