According to wikipedia, Osiris represented life, death, and fertility. I guess that's appropriate in a deep-Matrix-Whoa! sort of way. The Osiris dies, but in doing so, provides life for the people of Zion, and fertility too when you consider the rave in the second movie.
Oh, wait, did I just say the Osiris dies? Oh no! I spoiled the plot that's heavily implied in the title.
Wikipedia also says: The boss at the end of the Egyptian themed dungeon, Ruins of Ahn'Qiraj, in World of Warcraft is named Ossirian the Unscarred and has the features of a hawk. Well, that's good to know. I feel better knowing that.
Riff by Tom and Shane. (Yes, those guys.)
(Available in NTSC)