I sewed this bedside pocket for a Christmas gift for Tiger Lily. You shove the non-stick shelf liner between the mattress and box spring, and the pocket holds books, dolls, flashlights, or whatever a four-year-old needs while she's in bed. I made the pockets different sizes so that one would be large enough to hold a picture book.
I have a hard time keeping gifts for Tiger Lily a surprise because she's home with me all the time. As soon as she saw me laying out the fabric, she knew I was making something for her ("because it's pink!").
I used the concept from One-Yard Wonders, but I altered it to avoid using bias tape. I think my way was a lot faster and easier, but probably less cute.
I used a thrifted sheet from my stash, and some shelf liner that's been kicking around forever. There's a corner cut out of it, but I don't think that will affect its functionality.