FeedFlow is a simple Feed reader gadget that uses the Windows Gadget “engine” (Sidebar). It’s an open source tool and completely free to use, has a small memory footprint according to the developers and runs in Windows Vista and 7.
But if you have manually disabled the Windows Sidebar, then to run this you’ll have to enable it first. And the sidebar takes a decent amount of your RAM when running. So altogether, it cannot be considered a lightweight app, unless you’ve already being using the Sidebar feature in Windows.
However, if you already use it and looking for a lightweight feed reader, then “FeedFlow” is very handy though. Being a simple tool, the functionality is also a bit limited. But, it’s really easy to use and lets you configure your feeds and resize the gadget itself too.
Few main features …
*. The default size is too small for my needs and at first I thought it doesn’t support resizing (yikes!). However, when you move your mouse over to its top and sides, it reveals a resizing scrollbar, which you can use to set its size according to your needs.

*. Add/Edit/Remove Feeds.
*. Export/Import settings (including your feed addresses) with ease.
*. Has few built in themes.
*. Auto scroll feeds (disabled by default).
*. Hide feeds after reading (disabled by default).
*. Change update intervals.
*. Change feeds per page.
*. Change fonts and their sizes.
*. Delete the feed cache.
*. Hide “descriptions”.
*. Switch between feed URLs with ease.
That’s it!.
When you click on a feed’s title, it’ll open it in a new window (attached to its left side, as shown in the first screenshot). And so far it has rendered the web pages without any issues. When you click on a URL, it’ll open it through your default web browser.
If interested you can get it from this FeedFlow Google Code page.