The 1.4 version of NotLight for Mac was available to download on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. We recommend checking the downloaded files with any free antivirus. The most popular version among the application users is 1.4. The actual developer of this free software for Mac is Matt Neuburg. NotLight for Mac relates to System Tools.
From the developer:
NotLight is a simple Spotlight front-end substitute. You can do any kind of Spotlight search with this app; seven search keys are built in, and you can add more, and you can even view and edit a search as text if you like. You can use wildcards or not, specify word-based, case-insensitive, and diacritic-insensitive searches, and construct complex searches with AND, OR, and NOT.
You may want to check out more software for Mac, such as Libra, Mac ScanAndSweep or Curator, which might be similar to NotLight.