At our hackerspace we have a whiteboard, but we always lose our markers. This is because we do not have a pen holder to collect the markers. Sugru is easy component to create pen holders for our whiteboard.
Step 1: Shape Your Sugru
You can form the pen holder any way you want, then you can stick it to the whiteboard.
Step 2: Press Sugru on White Board
The Sugru will stick and you can test whether the marker place is good enough (and you can reshape flexible material if needed).
Step 3: Wait Until It Is Solid
Sugru retains its plasticity for thirty minutes and is self-curing at room temperature after approximately 24 hours (see https://en.wikipedia.org/wiki/Sugru)