I haven't heard of anyone using "geekily useful" so you can assume it is mine. I never used it before, and may never hence, but you can go ahead and do so.
Like "digit dust," I admire spur-of-the-moment coinages that convey a word picture.
My hope is that I could find the direct quote from Mr. Butner, if he coined the term. I have no reason to doubt that he did, but I would have hoped the writer would have quoted him directly, thus, "The price of a SnowGoose is digit dust if you look at it compared to the entire Defense Department budget." The way it is presented is good editing, but may lose some of the context. <shrug>
I wonder how little significance you need before you arrive at digit dust? But that is a further geeky meandering.