Cast videos directly from your Android Gallery, Dropbox or Google Drive with AirCast
AirCast, a new concept application from everybody's favorite Android hacker and developer Koushik Dutta, will let you play any videos from your Gallery, Dropbox and Google Drive on your Chromecast equipped television. Using your Android, you select a video from any of the three locations and use the share menu to cast it to your TV.
Koush has worked around the closed SDK issue by reverse engineering the Chromecast protocols, which means he is allowed to share this app for us regular folks to have a go with and test it. Apps using the official SDK are not yet allowed to be released under the current agreement users of the SDK are bound to.
You'll definitely want to give this a try, so grab the APK file from Koush's website right here and give it a look. Keep in mind that this application will expire in two days, but Koush has said he has plans to release a freemium version, a Chrome extension, and the code he used to make it all work in the future. Remember, you're testing this so be prepared to submit feedback for any bugs you may find. See the source link for more details.
Source: +Koushik Dutta