Sept. 24, 1991: Tribe Called Quest's Low End Theory comes out. While essentially an album for incredibly cool people, it includes the dorkiest moment in hip-hop to date: a 19-year-old Busta Rhymes growling "RRRRRROAW RRRRRRROAW like a dungeon dragon / Change your little drawers cause your pants are saggin'."

Sept. 2, 1995:I Wish by Skee-Lo hits No. 53 on the Billboard 200, propelled by its title single, a rap about having bad coordination and being short. Includes the immortal lines "Dag, y'all! I never understood / Why the jocks get the fly girls / And me, I get the hood rats . . . "

Oct. 31, 1997: Video game PaRappa the Rapper released in the U.S. PlayStations across the country run hot with youngsters' attempts to beat the All Masters' Bathroom Rap Battle level.

May 23, 2000: Del tha Funkee Homosapien, Kid Koala and Dan the Automator team up for their sci-fi hip-hop epic Deltron 3030. They would later gain favor with the cool-kid audience with the first Gorillaz album, but this original Deltron CD is the ultimate in high-profile nerd rap.

April 30, 2002: Blackalicious releases Blazing Arrow, which includes the track Chemical Calisthenics. A sequel-in- spirit to their famous Alphabet Aerobics, this one overloads the geek-o-meter with lines like "C-A-O-H-2 wine water solution of calcium hydroxide / Slobbin it, C-A-O lime will make bleach powder / Galvanic metal beats stomp out louder."

[Originally published in the Rocky Mountain News, Colorado, Nov 16, 2007]