For all you meantone fans out there (and you know who you are), here are some
meantone systems not already discussed. Rational implications are staring us in
the face here.

24: [49/48, 81/80, 128/125]
26: [50/49, 81/80, 525/512]
38: [50/49, 81/80, 3125/3072]
45: [81/80, 525/512, 2401/2400]
50: [81/80, 126/125, 16807/16384]
55: [81/80, 686/675, 6144/6125]
67: [81/80, 1029/1024, 9604/9375]
74: [81/80, 126/125, 4194304/4117715]
81: [81/80, 126/125, 17294403/16777216]