Here's an interesting variation on Project The Electronic Gas Tank in Capacitor section, this time the LED lets you see the effects of capacitor charging and discharging.
When you finish the wiring connections, put the two switch to ON. You'll then see LED 1 slowly begin to light up. After a few moments LED 1 will reach maximum brightness and glow with a steady light.
When that happens, set one switch to OFF. LED 1 will start to gradually fade out, eventually going completely dark. Take a look at the schematic. Can you figure out how this Project works? Give it your best shot.
See, there was nothing hard about that. (Unless, of course, you tried to read it without turning the answer upside-down!)