There must be at least one frightened teenager out there today. AP reports that U.S. investigators have identified a teenager as one author of a version of the Blaster worm and plan to arrest him early Friday (U.S. time). A witness reportedly saw the teen testing the infection and called authorities, an official said. The worm and its variants infected more than 500,000 computers worldwide.The “Blaster.B” version of the infection, which began spreading Aug. 13, was remarkably similar to the original Blaster worm that first struck two days earlier; experts said the author made few changes, renaming the infecting-file from “msblast” to an anatomical reference. Can’t help feeling sorry for the kid. He is going down.