I had old IKEA GRUNDTAL shelves lying around and I wanted a glass shelving unit for my modem and plants. It took me two evenings to complete and the cost came up to around $80. Looking back, I would have ordered the glass clamps from China for lower cost.
I like how simple it looks. Minimalistic, with no support beams needed. It looks modern and slick and I was able to choose my own shelf spacing based on my needs. The most important thing about this hack is to maintain low center of mass for stability.