LispCleaner is available for download on SourceForge now. It is totally free and cures most of the lisp virus infections caused by acaddoc.lsp, acad.lsp and acad.vlx files. Click here to visit LispCleaner project page on SourceForge.
With version 1.2, I added an option for not to backup lisp files. It also supports /nobackup command line argument, that can be used when run in silent mode. You can see more details about lisp cleaner on the project page.