On the heels of Andy's full list of modes, I've taken an an idea I had a while back and developed an automatic method for picking a shortlist of likely modes given a frequency.
I did this as a proof-of-concept for fldigi, to allow the short list of mode choices to be automatically configured by frequency. The idea is that if you are at 14.070, the list is likely the PSK derivatives; if you're up a bit at 14.074, the list would expand to include MFSK and Olivia. For info and a quick demo, see http://wa5znu.org/2007/08/bandplans for a demo of real data for 80m taken from bandplans.com and converted to machine-readable format, and a 10-line program. Leigh/WA5ZNU