Lana: In the earliest seasons, she was initially known as the Pink Princess because of her early wardrobe (and the fact that, by Season 3, the pinkness was arguably becoming a Running Gag until her wardrobe changed in Season 4). Super Kryptonite Woman or The Amazing Kryptonite Woman, after becoming walking Kryptonite. Also known as the "Squirrel."
Pete: Product Placement Pete, as his little bit of screentime was usually used to place products such as music from Lifehouse, the "Talon Mix" CD, and Stride Gum.
The episode "Doomsday" is often nicknamed "Failsday" for its rather anti-climactic ending.