No one outside of certain government circles knows exactly how much the wayward, school bus-sized satellite cost. The National Reconnaissance Office doesn't let taxpayers do recon on their black budget loaded with red ink. But by 2002, the program for this particular kind of satellite was threatening to outstrip it's reported $5 billion (with a B) budget. The so-called "Future Imagery Architecture" satellite was as much as $2-3 billion over budget.
Once in orbit, it never worked.
Then there's the cost of actually shooting down the $6-7 billion dollar paperweight -- sending three Aegis destroyers on the mission, modifying three SM-3 missiles (two more in case the first one missed) and actually shooting one of the $10 million missiles. Not to mention the logistics and support required from radar, communications and whatnot back on land.
Here's DoD vid of the launch and intercept.
That comes to nearly $20 million right there by most estimates.
At least we got a great fireworks show! (WaPo)