"Given five or six performance doublings since 1995 courtesy of improvements in clock speed, bus speed, architecture changes from 32 to 64 bit, additional cache memory and faster RAM, a conservative estimate would be that today’s single CPU 1-U “pizza box” web server is roughly fifty times faster than last decade’s model. Couple that with the 25x price difference for this pizza box, and your 2005 dollar buys you more than one-thousand times as much compute power as it did in 1995. Bandwidth is at least ten times cheaper than it was in 1995, floor space in the data center is seven times cheaper and enterprise-class storage is at least four hundred times cheaper than it was only a decade ago.
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What does this mean for a web-services company? The cost to deliver an application to an end-user has dropped dramatically for these companies and the cost to operate their data centers therefore has much less of an impact on their costs of operations and capex budget than it used to, which means their gross margins for delivering their product have improved significantly since 1995. For companies like Yahoo, Google and more recently, Technorati, this means the cost to deliver a page view or search results page has gone down dramatically, while the average size of a search-results page is perhaps only marginally larger since 1995."
See also: Software’s Top 10 2005 Trends: #3 Software As A Service – some internet business models can be revisited because some of the underlying assumptions that led them to fail are no longer true.