Easiest, quickest DIY ever! (If you have tools, that is.) Seriously—about 15 minutes.
I have a tiny worktable in the bedroom and I need to make good use of space. So for the cost of one board (about $2) and a free shelf, we made this:
...out of this:
1. Take off the drawer handles.
2. Measure and cut the board to fit. Think snug.
3. Test to make sure what you are going to put on the shelf actually fits:
Two screws on either side will hold it in place.