Instant Jam, a free-to-play Guitar Hero-like browser game that lets you play along to music stored on your hard drive, has been announced.
Instant Jam is from Las Vegas-based InstantAction, the company run by Westwood Studios co-founder Louis Castle.
The game is embeddable anywhere online. You can play it through a Facebook Beta Program launched today.
A non-Facebook public beta will be rolled out over the next couple of weeks, and will be available from the official site.
Instant Jam aims to re-create the console-quality Guitar Hero-style experience through the web.
It checks the songs in your music library to match them to suggested note charts, letting you play along with USB Guitar Hero and Rock Band guitars.
If all else fails, you can play along with your keyboard keys.
Instant Jam launches with "thousands of note charts supporting the world's most popular songs". The press release notes that number is more than all other console music-rhythm game franchises combined.
The note charts are all good and proper, InstantAction promises.
"Each note chart is designed by an experienced game design team to provide an immersive gaming experience that really makes you feel like you are playing a guitar.
"Instant Jam does not simply track song beats as some algorithmically generated programs do."
If you see a song on the game's playlist you don't own, you can buy it from Amazon or iTunes through the game and get "in-game value in excess of the cost of the song".
As is the social game way, you can buy virtual goods that "enhance" play, gift items and challenge your friends.
"We created Instant Jam because we believe people should be able to play along to any song from any band or genre they like, rather than be confined to a handful of pre-set songs chosen for the game they're playing," said Castle.
"We also strongly believe that games like other forms of entertainment media should be easier for consumers to discover, try, enjoy and share.
"Instant Jam embodies all of this and provides music lovers with a powerful new way to interact while experiencing their music."
Instant Jam will be available initially on the PC, with Macintosh and Flash versions to follow shortly.
Eurogamer interviewed Louis Castle at the Develop Conference in July, and discovered his hopes to make games like Call of Duty playable through a web browser in the future.
A video showing off-screen Instant Jam gameplay footage is below.