Android: One of the neatest things about Chromecast is the ability to launch videos on your phone and then stream them to your TV. If you don't have Chromecast, AllCast allows you to stream local videos from your Android device to any DLNA-compatible player.
Currently, the app is available for download as a self-destructing beta that will end in a few days, but a newer version should come out soon afterwards. In the meantime, the app allows you to play your own videos on the big screen, and support for other video types is planned for a future release.
AllCast - Beta 7 [Google+]