I like how complicated and interlinked the world is. Take, for example, one of my ball-point pens. It was assembled in China from a number of components:

1. A casing of polystyrene plastic manufactured following a process which took a hundred years to develop, from petroleum oil, for which people drill into the depths of earth & sea - and which exists only as a result of the deposition of organisms on top of organisms for millions and millions of years.
2. A tip of brass - made by mixing copper and zinc, both of which must be extracted from the earth and purified through complicated, labour-intensive, potentially dangerous processes
3. A ball of tungsten carbide produced by heating chemicals to half the temperature of the Sun several times, which is ground into shape using diamond cutters (probably themselves manufactured using a process involving extreme heat and pressure applied by very complex machines)
4. Ink made from a mix of glues, solvents and resins sourced from various parts of the world

So the manufacture of every part of this pen involves long processes, which require the involvement of hundreds of people - all of whom must be fed, watered and housed by yet more people, making use of tools and materials produced by yet more people. 

Millions of people were involved, and centuries of technological development required, to give me this pen - an exceptionally simple device (compared to, say, my laptop, cell phone, or alarm clock) and one which attracts almost no notice from me unless it happens to break or get lost. And yet, indirectly, the whole world is connected to me through it!