A new modkit has been made by someone named Stephen who blogs about the projects he's involved with. One of his latest is the GBA Consolizer http://stephens-projects.com/projects/gbahdmi/ which makes it possible to play your GBA on your modern HD television with no latency or lag just as if playing on the handheld yourself.
At this point you're probably thinking to yourself "hey jerk I connect my GBA to my GameCube with my 'Game Boy Player' adapter and play it on my TV everyday what makes this so special". The Game Boy Player does not hold a candle to this though if you read through the features and see how it's a digital output opposed to analog so stuff does not get screwed up.
Also another useful addition to this mod is the addition of a SNES controller port. That way if you do not want the authenticate Game Boy experience with the screen being a fraction of an inch away from the player's eyes because the tin LCD is now replaced with a giant widescreen television you now have the luxury of using a controller with a decent length cord to get a better view.
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