Analogue devices may seem anachronistic in this digital age but they're still the fastest and most effective tools in some situations.

Take. for example. Gramicci's Zip-O-Gage that is essentially a mini mercury thermometer on a keyring. This makes it easy to get an idea of the surrounding conditions without pulling out a phone by simply having the Zip-O-Gage clipped onto a backpack zip pull or on a lanyard.

The thermometer provides temperature readings in both sensible base 10 notches and mind-boggling freedom units. Either way. the higher the mercury. the higher the temperature.