TagSpaces - TagSpaces is an open source platform for personal data management. With TagSpaces you can manage and organize the files on your laptop, tablet or smart phone.
cdcat - The cdcat is graphical (QT based) multiplatform (Linux/Windows/MacOS) catalog program which scans...
allTags - allTags is a free, tag based file management application.
Cathy - An extremly small, very fast and easy to use media cataloging tool.
Elyse - The free version allows up to 30 tags.
Virtual Volumes View - VVV uses a relational database to store its data.