How about a 700 nitro? Scroll down to find it and check the price
for the gun and each single cartidge. There are some on this list I never heard of.

The .700 Nitro Express develops an average of 8,900 foot pounds of muzzle energy. However handloaders can push the cartridge to generate as much as 15,000 foot pounds in a modern bolt action. However, doing so makes the action of the rifle firing the cartridge nearly inoperable (especially in the case of a boxlock or sidelock rifle), while at the same time rupturing the casing, and primer of the cartridge. The average muzzle velocity of the cartridge is 2,000 feet per second.

15,000 fp!!!!

http://en.wikipedia.org/wiki/List_of_rifle_cartridges