Use a glass building block to make a decoration, by drilling a hole and inserting Christmas lights, then add some decorations on the outside of the block.
Step 1: Prepare to drill the glass block.
8 in X 8 in X 3 in glass block (Home Depot)
glass and tile drill bit 1/2 inch
Drill press preferably
and Eye protection
Step 2: Drill Glass Block
Step 3: Clean the inside of the block.
Make sure that you have on gloves in this step as the glass dust escaping the little hole will feel like a sand blaster on your hand.
Step 4: Insert lights into block.
Step 5: Lights On
Step 6: Add final decorations
The best way to finish the block would be to use a VersaLaser to etch a pattern on the front of the block. Here the ideas are endless, you could engrave a name on it and use it as a night light.
Good luck and enjoy your Light Block.