Been working on theory for this myself. Been thinking about using H2O/Mg heterogeneous (obviously) solution being shot out as a vapor, mixed with some kind of enzyme. This will stick to the wall with the adhesive powers of H2O and the enzyme, and stay together with the cohesive powers of the enzyme and the Hg. Thing about this, there will be no sticky residue, considering it's vaporized. If not, Gecko Tape will hit the markets relatively soon, although it really only works fully on a completely smooth surface. We could look into Hydrogen Bonding.