In a perfect world, anyone who sent in money for the novelty x-ray specs advertised in the back of comics would be gifted with the actual ability to see through solid stuff. In reality, we have to rely on the kindness of folks with real tech for a peek. So: Thanks, Smithsonian!
The cultural institution's National Collection of Fishes is full of four million aquatic specimens, and specialist Sandra Raredon has been doing radiography on them for almost 25 years. Now, 40 prints are part of a new exhibition called—what else—X-ray Vision: Fish Inside Out. Thanks to the internet (yay!), you can check out a cool selection on Flickr, each of which comes complete with a click through to an entry on the Encyclopedia of Life; there you'll find tons of additional info about each see-through organism, along with a pic of the creature in its normal, opaque state.
Here's a few of our faves:
Ogcocephalus corniger holotype (credit Sandra J. Raredon, Division of Fishes, NMNH)
All images: credit Sandra J. Raredon, Division of Fishes, NMNH