One LED closer to eliminating fluorescents from our office entirely:
Bright light for a fraction of the power usage of fluorescents and incandescents.
No maintenance for years to come. (Who was it that designed the fluorescent light fixture? Changing a bulb in one is far more difficult than performing endodontics on a calcified five-canal maxillary second molar in a gagging trismatic.)
Some rare earth elements, but no mercury. We threw the amalgam out of the office years ago, now here's one less mercury stream for the landfill.
LEDs are so cool.