But I think today's example is the best yet:
http://www.theatlantic.com/business/archive/2011/05/the-cost-of-bin-laden-3-trillion-over-15-years/238517/
"By conservative estimates, bin Laden cost the United States at least $3 trillion over the past 15 years"
Perhaps Tim Fernholz and Jim Tankersley mean, "hey, we found some batshit crazy conservatives who are willing to estimate the following". Because they certainly cannot mean, hey, this is probably a lowball figure.
I'm a little startled to find that Fernholz and Tankersley appear to believe that the military buildup that occurred under Bush is meaningfully attributable to bin Laden. There's every reason to believe that quite a lot of what happened (the Iraq War for sure) was going to happen no matter what the external circumstances were, at least if Bush had any say in the matter.
Surprisingly, the rest of the analysis in the article is even worse. At least this has given me a New Rule: if someone says "Conservative Estimate", the next numbers to appear will be laughably lunatic, risible and ridiculous, terribly twisted, and any number of other things. But they will _not_ be a conservative estimate in the commonly understood literal sense of the words.