And, within a script, you can start a child process and then disown it. Here's an example (written because the JSView Firefox extension assumes that any "executable" has an ".exe" extension, and this was easier than fixing the extension code.)
Code:
$ cat Scripts/kate.exe
#!/bin/bash
kate $* &
disown -h
The code starts
kate, disowns it after telling the child to ignore hangup, and then exits.