Tidy Tray tutorial at The Sewing Republic, which is a very simple project. You basically sew a square and then sew the corners together to create a little basket. I didn't change much, but did take a few shortcuts. First, I substituted fusible fleece interfacing so I wouldn't have to pin much. Also, I didn't mark full lines on the fabric and eliminated the stitching on the bottom of the basket. I just marked little dots equal distances in from each corner, and then folded the square on the diagonal to make the dots meet up. Sew a straight seam perpendicular to the finished edge, and you're done!
Then I experimented with making larger baskets with deeper sides. I didn't like how much the corners stuck out, so I folded them in onto the sides and then stitched them down.
The original squares on these two nesting boxes were 12.5 inches and 8.5 inches. I marked each corner at 2.5 inches before sewing and folding. I think they are cute - like little folded fabric boxes. So simple, and seriously quick. They are perfect as a little catch-all to hold spare change, jewelry, or whatever else you need to keep contained!