When people start referring to MIPS (Million Instructions Per Second) being turned into a commodity due to utility and grid computing, it sounds like the best thing since sliced bread. But if you really start to think about it, the idea becomes more and more ludicrous. We're somehow supposed to believe that MIPS will soon be listed on the Stock Exchange along with orange juice and crude oil.
Now think about this: If an abundant and unlimited supply of orange juice could reliably come out of a $2,000 19x19x1.75-inch metal box simply by throwing some electricity at it and keeping the temperature right, would orange juice ever be bought by the ounce again? If you could buy 1U box that cost you a three-months supply of gas but could spit out all the gas your car could use for the next four years, would you ever go to the gas station again for the honor of paying for a commodity? Yet, we are asked to believe that people would rather pay for MIPS hundreds of miles away at a cost where they could have owned the hardware after three months of renting MIPS. Then again, there will always be people who choose to rent their hardware.
Even ignoring the economic issues, it is very questionable if grid will even work for you in the first place. Grid computing is essentially a new word for an old concept, the concept of massively distributed parallel processing. There are actually very few applications that lend themselves to massively distributed processing -- SETI (Search for Extra Terrestrial Intelligence), some simulation software, and symmetric cryptographic cracking are a few examples but none of these are memory or disk I/O intensive. Take an I/O-intensive database application and I just can't see how that will work when it's hard enough getting a database to work in a controlled WAN let alone an uncontrolled one such as the Internet. Typical database I/O requirements are 300 megabits per second so it's a stretch to even get it to work on a super expensive high speed fiber optic WAN link that provides 150 megabits per second. Most Internet connections are capped at 1.554 megabits per second and your data is only delivered with best effort. The idea that you're somehow going to be able to tap a massive unused pool of MIPS on people's idle home and corporate computers for your typical business software is a non starter.