Things that have taken less time than Duke Nukem Forever's Development:
Pop Culture:

* The Beatles formed, released every single one of their albums and broke up. During this time they also toured the world several times.
* Led Zeppelin released 7 albums, 9 singles, and toured around the world, crossing international borders 27 times (not counting mainland Europe.)

Science & Technology:

* The Wright brothers designed and flew the first airplane.
* The theory of General Relativity.
* The United States' entire program to put a man on the moon, from Kennedy's challenge to the landing.

Wars:

* The American War for Independence
* The United States Civil War
* World War I
* World War II and the entire Manhattan Project.
* The United State's involvement in the Vietnam War.