A supplemental characteristic or feature for a product unnecessary to its basic and proper functionality; a frill; in some cases a "nice to have" add-on, in others a useless redundancy or completely unrelated & undesirable by-product
"Damn it... I just upgraded my finance software, and it installed thirteen demo apps. They should have made those addioptional. Now I can't find anything in all the desktop clutter, and I lost 3 gigs of hard drive."