A simple home-brew LED light fixture can replace traditional florescent fixtures mounted above a drop ceiling.
A pair of these now light a basement room using four 6-watt bulbs, replacing three florescent fixtures that used six 40-watt florescent bulbs. Twenty-four watts versus 240 watts, and light levels are still quite functional.
The LED bulbs here are rated as 40-watt incandescent equivalents. I find them every bit as bright as Edison style 60 watters. I initially tried a pair of 60-watt equivalents in this application, but the light was so harsh, it gave me a headache.
We pretty much limit 60-watt equivalent LEDs to porch or garage fixtures.
Clarification: These lights tied to the standard household wiring sytem, and are not part of the solar powered system noted in other posts.