This article came in on my email a couple of days ago, thought it might be of interest;
http://www.jlconline.com/how-to/foundations/pier-and-beam-foundations_o
A co-worker has a house that was built on steel piles. It is in an area that wouldn't have been built on a decade or two back. But land is scarce in Anchorage and people are finding ways to get a solid foundation. The house is fine, it's on about 40' of driven steel piles. The garage slab though was poured on grade. After many years of settling he's seeing a gap as the slab sinks below the sill.
Seems like overkill...I thought all you needed was a posthole digger and some 4x4s? ;D ;D ;D
Thanks for that Don. It goes a little beyond the typical DIY, doesn't it?