Wikipedia is updating its servers after a very successful drive for contributions. The page describing the hardware of Wikipedia is very interesting, especially the list of transactions per second, which is very similar to what SABRE (American Airlines famous CRS) had in the early 1990s (about 250 transactions per second). Highly unscientific and all that, but SABRE was the largest real-time system (unless, I think, you count the SACs SAGE system) in the world at the time and Wikipedia is a non-profit, run-by-volunteers encyclopedia.
It is easy to see the effect of Moore’s law on your own laptop or in the proliferation of single computers, but Wikipedia is a demonstration of the concequences for centralized computing. Neat.