Snackr sits on one of the four sides of your screen and scrolls through recent posts from sites which are input either by hand or by loading an OPML file. A nice added touch is that if there is an image in the post, it is included in the scrolling entry. There is a quick shortcut for minimizing the ticker in case it gets in the way and you can literally throw it around the screen. If you just grab Snackr and fling it in the direction of an edge of the screen, it will transform and stick there. Just try it to see what I mean.
Clicking on an entry brings up the full version of the post, readable and scrollable in the slide out window. This application becomes really useful when you narrow your feeds down to your mid to high priority ones and limit the items that it displays to a maximum of somewhere between 2 and 5 days old. If you have anything older than that, the posts start to become stale and irrelevant.
Snackr may be a distraction for some and overwhelming for others, but I really like having this extremely relevant river of news glide by on my screen. As Marshall mentioned, it's a pain to remove feeds if you have a lot of them that you need to unsubscribe from after importing an OPML file, so a batch remove feature would be a great addition in the future. Additional features, such as indicating new items in the river and the ability to change themes, are things that would make sense for future releases, but Snackr runs really well and is very functional, especially for a first release.
Snackr is was written by Narciso Jaramillo, who is a product designer for Adobe Flex and previously worked on version one of Macromedia Dreamweaver.