OverClocked ReMiX! All the great music you love, but remixed. You can learn many things here, like how to play Sonic 3 & Knuckles music on guitar, and Chrono Trigger: The Trial on said instrument.
SkyMarshall on Newgrounds Excuse some language occasionally, but other than that, SkyMarshall has a great way of keeping that old 4-16 bit sound with modern elements. And, some of his lyrics are cool. "Playing monty on my commodore, when the games were in their prime, let me take you back in time." Ahhh...
F-777 on Newgrounds Only the best techno I've ever heard. It deserves to be here. Even if you ignore the other links, click this one. It needs it. Really. It does. Yeah.