Italian astronaut Paolo Nespoli took some pretty heavy hardware with him up in his recent trip to to the ISS, leading to some of the most stunning photographs of the space station that we've ever seen. While we're insanely jealous of the opportunity to go into space, we're also left gaping at the gear they took up only to leave behind. According to Cosmic Log, Nespoli went up armed with (at the very least) a Nikond D3S, a Nikon D3S, a Nikon D2Xs, and a 24-120mm lens (with others to be sure). Of those, the D3x was used to photograph the ISS as he jetted off on the Russian Soyuz shuttle, at which point the camera and lens were left behind in the orbital module, to burn up in re-entry.
We don't know if the other two cameras and doubtless lenses were left behind on the space ship, but you can bet that they're never coming back to earth. Our back of the envelope calculations put those three bodies and single lens at just under $20,000 in street price — and we bet there are a few more lenses involved.
While $20,000 may sound like a huge amount to spend on hardware just to have it destroyed, keep in mind that putting items into orbit isn't a cheap endeavour. The cost of getting mass into space via a Soyuz launch is around $5300 per kilogram. With around 4.3kg in camera gear that we know of (those D3 models aren't light), that's more than $20,000 again just to get the cameras up there in the first place.
In 2009, NASA purchased 11 D3Ss with accompanying 18-24mm lenses, but NASA has said that the D3X left in orbit was provided by the Russians.