So, I assume since everyone has seen the finale, I have a theory about Lelouch. Now.. this may be stretching it, but:
The Cowboy is the power of immortality, which Vicious has. The captain of the ship, Jet, has the Cowboy. He transferred the Cowboy to Spike while strangling him in episode 21. Spike wanted this, and he deliberately told Faye not to interfere.
However, the Cowboy does not activate unless the reciever dies first. This is shown when the pirate kills Vicious after transferring the Cowboy to her. Jet's Cowboy activated when he shot himself. Here is one of the big misconceptions that most people have: The transfer of the Cowboy does not involve the death of the transferrer. The pirate was crazy and killed herself after she transferred her Cowboy. Ed was injured from the battle and died. So basically, after episode 21, Spike had Jet's Cowboy (inactivated) and Vicious' contracted Bebop.
When Spike got stabbed by Faye at the end, his cowboy was activated. What supports this is that Ein got Spike's memories when he touched him, just like Spike did when he touched Vicious back in Io. The only way this could have happened is his Cowboy activating. This pretty much confirms he has the Cowboy.
Unlike Vicious, and Jet, who lost their Bebops because the people who contracted them died, Spike didn't obtain Vicious' Cowboy and thus kept his Bebop, while having the Cowboy (which he obtained from Jet at the same time)
Spike, therefore has achieved COWBOY BEBOP.