You don’t need this software to hack an AppleTV but it makes things easier.

aTV Flash (black) is a user-friendly software package that supercharges your new black AppleTV, unleashing a plethora of new functionality. Don’t worry about the technical details – aTV Flash (black) is simple to use and safe for your AppleTV. Installation is a snap and doesn’t require any physical changes to the AppleTV.

MacUpdate has it for the sale price of $19.99 today only.  AppleTV (2010) went on sale for $89.99 at Amazon matching Best Buy so you are looking at $110 for the whole shebang.  If you have an old AppleTV, they’ve got you covered there as well.  Full features below:

Go Beyond iTunes Empower your AppleTV to play popular media formats including MKV, AVI, MP4 & many others.	Surf the Web Visit your favorite sites, stream HTML5 video, and update Twitter all on your TV. Your couch is your new workspace.
Enjoy DVDs the Simple Way Access all your DVDs on a single device for easy viewing. Includes full access to menus, special features, and 5.1 sound.	Discover New Music Find new artists you’ll love by accessing Last.fm radio stations, artist bios and slideshows.
Get Organized Automatically download and display cover art and other metadata from TheMovieDB and TheTVDB.	Access Media Anywhere Stream media from a Mac, PC or NAS device directly to the AppleTV. Includes support for AFP and SMB.

Create Video Playlists Keep tabs on your newly accessible media with custom playlists.	Know When to Stay In Quick access to weather forecasts lets you know if it’s a good night for a movie.	Stay in the Know Keep track of all your favorite news and blog sites by viewing RSS feeds on your AppleTV.
Easy Updates Updates are easily installed with just a few clicks through the native AppleTV menus.	Unchanged Original Features Why mess with what works?  All normal AppleTV features will remain unchanged.	Much, much more… Many more exciting features still to come!

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