Protective Baby Foam

  I have recently become a new dad, as my daughter was beginning to crawl around and now starts to learn to work she often falls and comes close to hitting herself on our furniture (e.g. coffee table).
  I think it shouldn't be too hard to create some type of semi-permanent hardening foam, that one could spray around sharp edges of wood / plastic.
  The compound would need to form a good seal but also be able to be easily removed when needed without doing damange to the underlying material.
  I would be interested in buying such a product if it were say under $5 for the can.