Because I have too much time on my hands, I went through all of the old threads and pages I could find about significant college-sponsored National Merit scholarships. Here's an updated list, sorted by what I hope is an understandable format. If you have a correction or addition to make, please speak up--it would really useful if this list or a similar list were kept up-to-date.
*Full ride is defined as minimum tuition/room/board.
*U=University, C=College
NMF FULL TUITION+
Publics
U of Alabama (NMF full ride & NMSF full tuition with 3.5 GPA guaranteed)
U of Alabama-Huntsville (NMF full ride & NMSF full tuition guaranteed)
U of North Alabama (NMF full ride & NMSF full tuition+ guaranteed)
Alabama State U (full ride guaranteed)
Auburn U [AL] (full tuition+ guaranteed)
U of Arizona (full ride guaranteed)
Southern Arkansas U (in-state full ride/OOS full tuition+ [full ride - 2.5k] rolling)
U of Central Florida (NMF full tuition+ & NMSF 9k guaranteed)
University of Idaho (NMF full ride competitive [25])
Eastern Kentucky U (in-state full ride & OOS full tuition- guaranteed)
U of Kentucky (full ride 1st year & full tuition+ remaining 3 years guaranteed)
Louisiana State U (full tuition competitive)
U of Maine (tuition- competitive)
Wayne State U [MI] (full ride competitive)
U of Minnesota-Morris (full tuition guaranteed)
Mississippi State U (NMF full tuition+ & NMSF full tuition- guaranteed)
U of Southern Mississippi (NMF/SF full ride competitive)
Southeast Missouri State U (NMF full ride guaranteed, NMSF full tuition- guaranteed)
U of Nebraska-Lincoln (full tuition+ guaranteed)
Cleveland State U [OH] (full tuition guaranteed)
Youngstown State U [OH] (full ride with 30 ACT/1300 SAT competitive [40])
Ohio State U (full tuition competitive)
U of Oklahoma (full tuition+ guaranteed)
Oklahoma State U (full tuition+ guaranteed)
U of Memphis [TN] (NMF [9k + OOS waiver] & NMSF [7.5k + OOS waiver] full tuition+ guaranteed)
U of Houston [TX] (full ride guaranteed)
U of North Texas (full ride competitive)
U of Texas-Dallas (full tuition+ guaranteed)
Texas Tech U (OOS full tuition [12.7k] guaranteed)
U of Texas-Tyler (NMF full ride & NMSF full tuition+ guaranteed)
U of Wisconsin-Oshkosh (in-state full ride guaranteed [~4k OOS tuition difference])
Privates
Abilene Christian U (full tuition guaranteed)
Alfred U (full ride guaranteed with top 5% rank, otherwise full tuition/ride competitive)
Andrews U (full tuition guaranteed)
Baylor U (full tuition guaranteed)
Birmingham-Southern C (full tuition competitive)
Denison U (full tuition competitive)
U of Evansville (NMF full tuition & NMSF 75% tuition guaranteed)
Faulkner U (NMF/SF full tuition guaranteed)
Fordham U (full tuition+ competitive)
Harding U (full tuition guaranteed)
Liberty U (NMF full ride & NMSF full tuition guaranteed)
Long Island U-C.W. Post (full tuition competitive)
Oakwood U (NMF full tuition+, NMSF full tuition, & NMCommended 80% tuition guaranteed)
Oklahoma Christian U (full ride guaranteed)
Pacific Union C (full tuition guaranteed)
Sterling C (full tuition guaranteed)
U of Tulsa (full ride guaranteed)
Wesleyan C [women only] (full tuition competitive)
Westminster C [UT] (NMF full tuition & NMSF half tuition guaranteed)
NMF HONORABLE MENTIONS
Publics
U of Central Arkansas (12k guaranteed with 3.25 GPA)
California State U-Fullerton (in-state only: full tuition+ guaranteed)
California State U-Long Beach (in-state only: full ride competitive)
University of Florida (OOS tuition waiver guaranteed)
New C of Florida (17.5k guaranteed)
U of Kansas (in-state only: 10k guaranteed)
U of Louisiana-Lafayette (unclear -
UL Lafayette: Academic Scholarships: High School Seniors)
U of Cincinnati (in-state full tuition+ [OOS 14k difference])
Wright State U [OH] (in-state only: NMF full ride guaranteed, NMSF/Commended full tuition guaranteed)
U of South Carolina (in-state up to 10k, OOS up to 6k + OOS tuition waiver)
U of Vermont (in-state NMF full tuition, OOS 10k guaranteed)
U of Wisconsin-Eau Claire (full in-state tuition guaranteed)
Privates
U of Dallas (NMF 14k, NMSF 12k guaranteed)
Rochester Institute of Technology (15k guaranteed)
U of Sioux Falls (full ride competitive [1])
U of Southern California (half tuition guaranteed)
Southern Methodist U (half tuition + 2k guaranteed)
St. Olaf C (7.5k guaranteed)