I was exploring some caves on my map when I thought, "It would be nice if I had some sort of probe or could see through stone so I could know if there are any nearby caves to mine into." Since there is no radar or probing device, I did the latter. these are the results:
I'm not sure if anyone else has done this before or not, but I still found it to be pretty cool. Here is the tile set I used if you are interested.
It's designed to fit the rest of my rainy skins, as well as replace glass with grating, so its near-useless to anyone that doesn't have the rest of the skins. I plan on releasing em eventually, though there are several others out there that are probably much better in quality and style...
Anyway, this did just give me an idea of making a wire frame texture mod which may look pretty neat. I'll likely update this post with it when I finish it.
Edit: Done before or not, here is a wire frame and solid color tile set.