When Newzie is minimized, popup notifier enables you to read new posts as soon as they are retrieved. It pops up out of the system tray and stays put for a while till you keep your mouse cursor out of it. Then, it automatically disappears and allows you to continue what you were doing.
Shown in the sample screenshot above, all new posts from one source are grouped together and listed one after another. When you keep your mouse over any post for a second, a small panel pops up and shows more of the content of focused post, as shown below.
Note that keeping the cursor a little bit longer marks that focused post as read, automatically.
If you like to read more about shown post, you can click the title of that post which opens up its associated webpage in your default web browser. Or you can make a right click on any post to get more options, which can be applied on that post, such as deleting it.