Madness also had a pretty big hit in the U.S. with "It Must Be Love" (it's in TV commercials all the time), "One Step Beyond", and "House of Fun", so, not so much one hit wonders.
Thomas Dolby also had more than one hit (Europa and the Pirate Twins, Hyperactive, One of Our Submarines, Abilty to Swing), granted none as ingrained into pop culture as "She Blinded Me With Science", but still considered hits.
Kahlenrules, I think that the "Saturday Night" song you're thinking of is by the Bay City Rollers. As far as the U.S. goes, one hit wonders (yet they managed to get a 1970's Saturday morning TV show out of it).
Both Gary Numan and Soft Cell seem to have their one hit wonders pop back up every 10 years or so. Cars was also covered by Fear Factory with Gary actually singing on it. Tainted Love has popped up on club charts several times with remixes to fit the sound du jour.
that 70's song "Get Off" is by Foxy
Now, some of my favorite 1 hit wonders are -
Black Velvet - Alannah Myles
96 Tears - ? and the Mysterians
2 of Hearts - Stacy Q
The Gentleman Who Fell - Milla