This is lovely: Russell Seitz calculated how much the Internet weighs, by estimating how much energy is used each day to run it. The result?

A statistically rough (one sigma) estimate might be 75-100 million servers @ ~350-550 watts each. Call it Forty Billion Watts or ~ 40 GW. Since silicon logic runs at three volts or so, and an Ampere is some ten to the eighteenth electrons a second, if the average chip runs at a Gigaherz , straightforward calculation reveals that some 50 grams of electrons in motion make up the Internet.

Applying the unreasonable power of dimensional analysis to the small tonnage of silicon involved yields much the same result. As of today, cyberspace weighs less than two ounces.

I'm coming to this one a month late, but that's just terrific.

(Thanks to the After School Snack blog!)