I recently moved into a house with a "cut" in the wall between the master bedroom and master bathroom. It's a ledge about 8 feet high running about 2/3 of the wall between the two rooms.
The master bedroom has a ceiling fan with a 4-bulb fixture and the bathroom has two vanities with 6 bulbs each. I fitted all of them with CF bulbs and the output - especially in the bathroom - is impressive to say the least. So impressive that it trashes my night vision should I need to relieve myself at night or if I'm otherwise awake.
I found some Cree XR-E LED's mounted to MCPCB's left over from another project and decided I could use them to illuminate both rooms with indirect light by mounting them on the ledge pointed towards the ceiling. I had some ~1" x 12" aluminum strips scavenged from the scrap bin from another job years ago that could mount them and help with heatsinking.
After tinkering with the idea for a few days, I settled on a basic circuit design:
I had initially thought about doing something fancier, but two brightness levels separated by a factor of 10 has ultimately worked out for the best.
The details of the installation took up more time and effort than I thought it would, but it turned out quite well.
My oh-so-clever switch and power supply setup
One of two arrays
My awesome assembly technique up close - thankfully this is all out of sight from the ground
It works really well and chews up less power than a single CFL bulb. Low is more than enough to navigate both rooms and high is almost bright enough to read by in the far corner of the bedroom.