NY Times has an excellent article about the change to mobile IT, but it also gives some historical perspective:

In 2004, only 2 percent of notebook computers sold in the United States cost less than $800. In 2008, some 35 percent did, according to data collected by the NPD Group, another research firm.

Prices for desktops, which averaged about half the price of notebooks five years ago, had less room to fall, but indeed they have. At Fry’s, an eMachines system, made by a unit of Acer and having 3 gigabytes of memory and a 320-gigabyte hard drive, sells for $379.99. It isn’t even the least expensive one on the shelf. Hewlett-Packard, under its Compaq brand, offers a slower model with less memory for only $269.99.

The move to less expensive machines highlights that we do not need a powerhouse on our desks to do the job. Thin clients fit in well with this. If you are seeking the lowest cost computing, there is nothing lower in cost than a thin client. Retail prices of monitors/keyboard/mouse are about $160 here and a thin client can be had for about $80 so $240 per seat plus about $25 worth of server comes to $265 is at hand. There is no place to hide hundreds of dollars worth of proprietary software any longer.