Selvin, P.R.
The renaissance of fluorescence resonance energy transfer.  Nature Structural Biology 7: 730-734 (2000).

Recent advances in fluorescence resonance energy transfer have led to qualitative and quantitative improvements in the technique, including increased spatial resolution, distance range, and sensitivity. These advances, due largely to new fluorescent dyes, but also to new optical methods and instrumentation, have opened up new biological applications.