Originally Posted by Tree
I have seen that on here! it's awesome 8D
I actually realized I saw it on another forum
(hope it's not an excessively bad faux-pas to post one link to another forum). Apparently the hot glue didn't last but there are surely other, better ways to glue rocks together than hot glue (like Krazy Glue Gel, I'm pretty sure that would work well and it's known to be fishtank-friendly).
Here's a pic they had posted, though:
A couple of slate tiles are cheap and Home Depot, etc. I have to try this sometime!