DocFetcher - DocFetcher is a portable German/English open source desktop search application.
mlocate - Indexes filesystems allowing you to search for files.
SMF – Search my Files - SMF - Search my Files v13 is the fastest duplicate files finder and a multi-dimensional - file searcher, - file copier / mover, - file deleter / eraser, - and
fd - A simple, fast and user-friendly alternative to 'find'.
Everything by Voidtools - Everything. Locate files and folders by name instantly. Everything. Small installation file. Clean and simple user interface.
NTFS-Search - This tool enables users to search their NTFS formatted harddrives within seconds.