Pocket Razor
When life throws a spanner your way it's important to lay off the acid. Life as a general concept has no arms and therefore cannot throw a spanner your way. Impressions you may have that it is doing otherwise are likely to be more to do with the ingestion of powerful narcotics, or due to severe mental problems. However, should life as a metaphorical concept metaphorically throw a metaphorical spanner your way metaphorically, it is important to keep calm and maintain a cool head.
Having a hot head during one of life's many crises can lead to sweaty face, which with people walking on their foreheads so much these days, can lead to the individual slipping over and contracting face cancer. Many people like to keep a pocket razor on them at all times in case of such a situation. Should a potentially threatening situation the pocket razor can be utilised to shave off any unecessary hair, skin, or brain that may be keeping the head too warm to adequately deal with the obstacle they face. The blood rushing to their heads from walking on their bonce all day is usually a large benefactor of the balminess, and the razor's sharp left edge is often used to open up a couple of veins to make the head cool again.
It took just two weeks after the Pocket Razor garnered popularity for the human race to become extinct. Mysteriously, everyone had died in shaving related accidents. However with the Pocket Razor so widely available unsightly armpit hair has never again been considered a problem.