I never gave it a thought. How much can pulses of energy moving across space and wires actually weigh? Here's an article about another article that attempts to answer the question of how much the Internet weighs.

Read along and follow the directions closely as you can. If you're a math genius then this might be a fun experiment to work through. You try to guess what the Internet weighs by reading through what the author has to say. The answer is at the bottom.