My TT has very few shelves or storage.  I have been staring at the back of my dinette seat thinking I have 5 inches of room to the edge of the door that I could do something with.  Well, I finally did something with it.

[IMG]http://i1357.photobucket.com/albums/q752/CamperDude/shelf%202_zpsn5swfphq.jpg[/img]

Three metal shelves that are exactly 5 inches wide.  They were $4 each.  I staggered the shelves to make room for the fire extinguisher. 
[IMG]http://i1357.photobucket.com/albums/q752/CamperDude/shelf%205_zpswczmxawi.jpg[/img]

This is the inside of the back of my seat.  There is a hollow section in the back of the seat.  There was a wood frame on the edge but I needed to fish a piece of wood for support in the middle. 
[IMG]http://i1357.photobucket.com/albums/q752/CamperDude/shelf_zpseiuswf6k.jpg[/img]