Read It Later (download), the bookmarking meets productivity tool has a new iPhone app out (review it). It lets you sync up with your desktop reading list and pick up stories while away from your computer. But the real reason to get it, is that like the desktop version it lets you save stories for offline reading, giving you a way to catch up on content even when you're away from a sturdy data connection.
There's both a free and pro version. The pro version, which costs $2.99, adds in things like a bookmarklet for saving links from Safari, a sharing tool to post articles to external bookmarking sites, as well as a full screen browsing mode that gives you more screen real estate than you get in Safari. You can also set it to ignore the iPhone's accelerometer, which lets you read certain content sideways or upside down which can be useful for things like photos.
Here's a demo:
The company also recently released an API for developers to build Read It Later integration into their own apps. This means developers of RSS readers, or even news publishers could give readers who are also Read It Later users a way to save their content for later viewing.