My simple solution was to canibalize a cheap Breadboard to get two expandable PrototypingShields with some additional features.
What I used:
2 Pieces of Veroboard (<1$)
28 PinHeader (<1$)
28 femaleConnectors (<1$)
and some epoxy to get it smooth and fixed
Step 1: Soldering the Shield
Firstly I cutted the right number of pinheaders.
After putting them into the Arduino connectors, I saw the difference to my 0.1" spaced veroboard.
I bent the headers a little bit as you can see in the second picture.
Now the pins are ready to solder.
As you can see in Pic4 I cutted the veroboard with one hole space to the border, to solder the female connectors later.