There has been some interest in digital EQ and crossovers. If you would like to find out about the lastest check this out.
Invented by the guy who co founded Fairlight, so if that's anything to go by its very very nice.
Ian
http://www.deqx.com/index.html
http://www.deqx.com/press-events/press-jan-04.html
The DEQX Calibrated™ PDC-2.6 Processor is a 2-input, 6-output digital processor offering individual driver correction with extremely high order digital crossovers (typically 100dB/octave, but up to 300dB/octave) in addition to necessary room correction.