Haloid is quite possibly the most interesting Halo-related fan movie in existence. It manages to combine multiple genres and provide non-stop action as well as answer the question, “who would win in an ultimate showdown, Master Chief or Samus?”
While the answer to that very question might not be what most of us had in mind, it's definitely worth checking out. Whether or not you enjoy the Halo or Metroid games, you can still get some enjoyment out of Haloid -- the creator, Monty Oum, made sure of that.
I don't want to completely spoil the ending, because if I did, you would either call me a total liar or suddenly get the urge to plant a bomb in my mailbox for ruining the final sequence. Both outcomes would bode badly for me, so just sit back, relax, and watch this entertaining tale unfold.
[Thanks, Charlie and Irving!]