There are a few bands with the name, including the following:
They did not record under the name U2 because Brian Eno was the primary composer while Bono, The Edge, Clayton and Mullen were, as they used to say, Passengers of his ship.
The group made one album called Original Soundtracks 1, ostensibly a compilation of music the band composed for various films but most of the films were made-up as in-jokes by Eno (although a few of the films did exist, and since their release some of the tracks have been used in other real films such as Michael Mann's "Heat.") Music on this album is more similar to music recorded normally in Brian Eno's solo career than on U2 albums. It is very electronic and experimental.
The track "One Minute Warning" was used in the end credits of the first "Ghost in the Shell" anime movie from 1995. The film makers specifically asked the band to make the song for the film.
For U2 it was the next big step into experimental music world after recording Achtung Baby and Zooropa.
2) There is also an Italian electronic disco band of the same name who released albums from 1979 - 1986.
3) A currently-performing female fronted hardcore band from Frederick, MD.
4) The Passengers were a late-1970s Brussels postpunk / new wave band that later became better known as The Names
5) An Australian band from Sydney fronted by Angie Pepper active in the late 1970s and early 1980s. Their first single single "Face with no name" was released on Phantom Records in the late 1970s. They released vinyl and a split CD with Angie Pepper solo material on Citadel records.