Evernote (or similar) serves this function well, even better than a "favorite" because I can save/clip things from other sources. i.e. when I have time to read all the things I thought looked interesting I only need to to go Evernote, not to multiple sites.

A long press on Twitter's native [Android] app and selecting "Share via..." will allow you to easily/quickly save it to Evernote (or whatever similar service you may use).