The excellent ReadNow application, which allows you to easily read articles from your Instapaper and Read It Later articles on your Mac, has been pulled from the Mac App Store "...because of an infringement letter." Developer Michael Schneider added "[i]n my current situation I'm not allowed to provide any further information."
The good news is that if you have already purchased the app, you can still download it from the "Purchases" tab in the App Store.app even though the iTunes page for ReadNow now leads to the message, "Your request could not be completed."
However, as I waited for the Mac App Store to load on my iMac this morning, I found myself wondering "What would I do if I couldn't re-download it from the Mac App Store?"
Fortunately I have the app on my MacBook Air, so I could go to /Applications/ReadNow.app and then select File » Compress "Read Now" (or control+click the app and choose "Compress" from the menu).