Tiny little USB Bulbs that come in bulk ready to break off a larger PCB. Perfect for carrying around with your powerbank.
I bought these little USB LED torches on eBay for just 4 USD. That got me 10 of them and free worldwide shipping from China. Considering many shops sell similar items for around a dollar a piece, it’s a pretty amazing price.
You can use them with AC wall chargers, laptops, in-car USB chargers and of course portable power banks. They consume such little power that they’ll run for literally hours or days on even the smallest powerbank.
I measured the power consumption of this little LED light using my Portapow USB watt meter.