Do you scoff at hotel paintings? Do you dismiss garish works of art in second-hand stores? Is there a stack of old frames in the attic that you’ve let go ignored for decades? Well, get it together and have that shit appraised! There’s a whole world of lost, hidden, and buried artwork out there just waiting to be discovered—these stories are pricey proof. Here are 10 of The Biggest Accidental Art Discoveries of All Time. And maybe pay more heed the next time your crazy uncle says that landscape above the mantle is a real Picasso.