Modern LEDs are bright enough at low current to use as directly mains powered indicators with minimal circuitry. The slight downside is that with a simple resistor circuit the vast majority of the power gets wasted as heat. But the current is so low anyway that it doesn't really matter. Here are some simple ways to drive LEDs from 110V to 240V with minimal circuitry. I tend to recommend running resistors at around half their rating at worst as it means they will last a long time and not discolour too much with age. Note that I was working with open live connections to demonstrate the circuitry. I recommend wearing dry gloves when working with open circuitry and ensure your work area is RCD/GFCI protected as my bench is. If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:- http://www.bigclive.com/coffee.htm