Instant RSS Notifier 1.5.1 for Mac could be downloaded from 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. This free software for Mac OS X was originally designed by Rocky Sand Studio. The software lies within Internet & Network Tools, more precisely Browsers.
From the developer:
RSS Notifier turns OS X's Notification Center and your menu bar into an RSS Feed Reader.
You may want to check out more software for Mac, such as RSS Notifier, Feed Notifier or RSS Bot - News Notifier, which might be similar to Instant RSS Notifier.
Browser plugins
RSS Tools