I want to say the only highway I've "clinched" is I-565.
Guess I might as well update my list of entire routes I've clenched:
I-565 (AL)
I-759 (AL)
I-440 (TN)
I-359 (AL)
Alt. US 72 (AL)
Business US 231 (AL)
AL 34
AL 35
AL 235
AL 255
AL 759
TN 121 (IIRC)
TN 122
FL 12
FL 30A
Did some thinking late last night, and I'm fairly certain this is now my full list:
I-16
I-165 (Alabama)
I-359
I-440 (Tennessee)
I-475 (Georgia)
I-565
I-580 (Nevada)
I-675 (Ohio)
I-759
I-840 (Tennessee)
I-985
Alt. US 72
Bus. US 231 (Alabama, Tennessee)
Bus. US 411
Truck US 411
AL 24
AL 34
AL 35
AL 40
AL 67
AL 93
AL 124
AL 139
AL 173
AL 191
AL 205
AL 208
AL 255
AL 257
AL 279
AL 759
FL 30A (Gulf County)
FL 73
GA 39 Spur
MS 76
NV 342
Truck TN 7
TN 122
Partial clinches of a highway, but a full clinch of it in that state:
I-20 (Georgia)
I-24 (Georgia, Illinois, Kentucky)
I-59 (Georgia)
I-65 (Alabama, Kentucky, Tennessee)
I-71 (Kentucky)
I-77 (South Carolina)
I-81 (Maryland, Tennessee, Virginia, West Virginia)
I-90 (Idaho, Montana, Washington, Wyoming)
US 72 (Alabama, Mississippi)
US 280 (Alabama)