So a coworker gave me this idea and it was awesome!
All you do is buy a few subway tiles from Home Depot (under a dollar each) and decoupage something on top whether it's scrapbook paper, pictures, or fabric. Cover the tiles with around 3 coats of decoupage and then spray them with an acrylic sealer. Then put those round felt pieces on the bottom (also from Home Depot) to make sure they don't scratch the table.
Here are some I made for my place using scraps from things I've saved from our travels combined with some scrapbooking stuff I had around:
I also made some really cool ones for my brother's girlfriend. I stole a few pictures from her Facebook of her and my brother and printed them out in black and white and decoupaged them on the tiles, they were so cute!