Entire books have been written about the BCS, so there's no need to re-litigate its history here. Instead, I'll highlight two areas: the computer rankings that comprised a part of it, and how some fans have managed to keep it "alive" in recent years.
[insert names of each, plus the years they were active]
Asher Feldman at @BCSKnowHow (Twitter account required, sorry), produces weekly "simulated BCS" standings as if the BCS were still in use. He uses the AP poll instead of the Harris Interactive poll, but otherwise follows the exact same methodology that was in place from 2004 to 2013. He provides great details and analysis, so you should check out his feed. For now, I'll only leave below his image comparing the final top 25 of the simulated BCS and the CFP committee at the end of the 2023 season:
As of December 29
1. Michigan (13-0)
2. Texas (12-1)
3. Washington (13-0)
4. Oregon (11-2)
4. Alabama (12-1)
6. Ohio State (11-2)
(more...)
As of December 30
1. Houston (12 - 0)
2. Purdue (12 - 1)
3. Connecticut (11 - 2)
4. Arizona (10 - 2)
5. BYU (11 - 1)
6. Memphis (10 - 2)
7. Clemson (11 - 1)
8. Florida Atlantic (10 - 2)
9. Marquette (10 - 3)
10. Duke (8 - 3)
(more...)