The first invention is soap. This simple yet effective combination of fats, ash, and water has been critical for hygiene and disease prevention for millennia. It has massively reduced bacterial infections, saving countless lives and preventing incalculable economic losses from illness. Have you ever lived somewhere where there was a shortage of soap and would you like to comment about it?

The next invention is barbed wire. It solved the problem of affordable fencing in the American west by providing an inexpensive way to protect crops from livestock and demarcate property lines. It enabled the rapid, profitable development of agriculture in areas without easy access to wood for traditional fencing. Can you imagine what life would be like without barbed wire?

This last one is everywhere in the UK but much rarer in Canada. I wish it was everywhere. Cat's Eyes (Road Reflectors) were Percy Shaw's "gift" to mankind. His invention of reflective road safety devices provided a simple yet effective solution for illuminating roads in the dark or fog. They have saved countless lives by improving road safety, making its inventor wealthy and becoming a universal standard for road infrastructure - a standard that is not being met in Canada. Do they use cats eyes where you live?

Can you think of an invention that was simple to make yet had a powerful impact? If so will you comment about it?