I thought, I share this with you all.  
I am using a tool box that is originally made for fishing.  It is the- "Woodstream" Trunk style, 3 drawer - kind.
Plastic box and the three trays make it perfect for putting the smaller tools into place.
The bigger ones are in the bottom, but without the small compartments of the trays it would be just an other bulky box.  
I find it most useful and practical.  I travelled with it cross country on planes and had it in my car for years, loaded it with fifty pounds of tools.
I strongly recommend it for keeping the most important tools.  Small and most practical.
Size is 2x1x1
Zoltan