I don't know whether this should go under the Cave Story topic or not, but I think that the community's big enough to have it's own thread, plus the Cave Story thread's been dead for forever.

I've been playing some mods of Cave Story recently, and I think that they're a cool take on the game, and showing what the game can do that Pixel left out. Two good ones I've found are:

Jenka's Nightmare (Link to download), where you go back to the island in the sky a year after the events of Cave Story. And...

The Mimiga Army (Link to download), where you are a Mimiga named Abert in the events after Quote leaves with Kazuma on the dragon in the Bad Ending.

Have fun, and leave more good mods below. As long as they aren't viruses.