KHQA-TV (CBS) in Quincy, Ill. did some pretty notorious pre-empting in the early 1980s, much of it due to the station's commitment to carry the Illinois high school basketball tournament in March of each year (which also led to the station pre-empting some of CBS' coverage of the NCAA Basketball Tournament). The coverage of the Illinois tournament was particularly annoying due to half the station's coverage area being in Missouri (also a chunk of southeast Iowa). The boys tournament would take two weekends (Class A the first weekend, then Class AA on the second), with limited coverage of the girls tournament occurring on an additional Saturday.
Similar to WAGM, which an earlier poster said pre-empted part 1 of "The Incredible Hulk" episode, "The First," KHQA carried part 1 of the of the episode, but pre-empted part 2. (the station carried both parts when CBS reran the episode in the summer). KHQA also pre-empted the infamous episode of "Dallas" in which J.R. was shot (KHQA aired that episode on a tape-delay the next night at 11:00, although it was scheduled for 10:30. It was pushed back due to an overrun of the Illinois tournament earlier in the evening). In somewhat of an ironic twist, KHQA sponsored a "Who Shot J.R." contest over the summer and early fall.
The Illinois tournament also led KHQA to pre-empt CBS' annual showing of "The Wizard of Oz" two years in a row (1982 and 1983). The second year (I'm sure after multitudes of viewer complaints the previous year), KHQA aired the movie on a tape-delay, with that airing at least 8 days after the CBS showing. In the following years, CBS's scheduling of "The Wizard of Oz" always fell outside of the Illinois high school tournament, although there were years where it just missed by a week. In those years, CBS always scheduled "The Wizard of Oz" on a Friday or Saturday night late February or March, and the Illinois tournament was on Friday and Saturday nights
The CBS Saturday night shows would also be totally pre-empted.
Since "Dallas" and "Falcon Crest" had continuing storylines, KHQA always showed them on tape-delay if pre-empted. "Dallas" was always shown Saturday night at 10:30. "Falcon Crest"'s alternate timeslot changed from year to year...sometimes it would follow "Dallas" late night on Saturday (11:30), or would be shown Sunday at 10:30 PM. "The Incredible Hulk" and "The Dukes of Hazzard" (depending on year) were totally pre-empted due to Illinois basketball.
The Illinois high school tournament also aired games on Friday and Saturday afternoons. Initially, KHQA just pre-empted the CBS soaps on Friday afternoon, and whatever sports programming CBS had on Saturday afternoon (most years this included NCAA tourney coverage). Sometimes KHQA would join the Saturday NCAA coverage in progress, and some years they would just pre-empt whatever part fell outside of the Illinois basketball coverage with syndicated shows, particularly if the NCAA coverage started before the Illinois coverage. For a few years, when KHQA was still showing mainly sitcom reruns in the afternoon, KHQA would tape-delay "As the World Turns" and "Guiding Light" to 3:30 and 4:30, respectively, with "Capitol" being pre-empted. When KHQA started showing more first-run syndicated shows in the afternoon (i.e. Oprah), the Friday soaps were again totally pre-empted.
KHQA stopped carrying the Illinois high school tournament sometime in the early to mid-'90s. By that time, the popular CBS shows that always fell victim to the tournament were long gone.
KHQA also pre-empted "Rudolph the Red-Nosed Reindeer" two years in a row, I believe in 1984 and 1985. The first pre-emption was the result of KHQA showing a Red Cross or Salvation Army special. The second year, Rudolph fell victim to a Billy Graham crusade.
WHBF-TV in the Quad Cities was another CBS affiliate that carried the Illinois high school tournament for many years. Subsequently, the station's Friday and Saturday CBS pre-emptions were identical to that of KHQA. However, WHBF gave up (or lost) the rights to the tournament in 1984 or '85 when WQAD (ABC) took over coverage in that market.