1. FlipFlop Set/Reset
Press one button the output goes to a high level, press the other and will go low.
2. PWM with variable frequency
By changing the time the capacitor need to charge(capacitance vrs resistence), the frequency of the output oscilation changes
3. PWM with variable duty (everycircuit can't handle it)
Same as the other, but this time, the frequency is fixed because you don't change the potentiometer value, you can reduce or increase the charge time of course, but the discharge time will be inversionally proportional to that.
4. Monostable multivibrator
Pressing the button will discharge the capacitor and the output will go to a high level untill it charges again through the resistor, pressing the button before that resets the "timer"
