While I certainly wouldn't say Satan is a nice guy (after all, his whole point is that he's the source of all evil, right?), I can't help feeling somewhat sorry for him, at least as he's portrayed in popular culture and religion. I mean, if the Bible is correct, he obviously knows the scriptures and is aware that he's going to lose in the end (which can't seem that far away to an immortal being), but he just keeps soldiering on anyway. I guess the Norse gods were sort of similar, in that they all knew they'd die at Ragnarok, but still went on with the deitizing. It's one of the worst kinds of fatalism, isn't it? Mind you, Satan certainly keeps busy, what with his ruling Hell, running the music industry, controlling most of the world's religions (all of them except whatever one the person talking at the time believes in, apparently), disguising himself as every pagan deity, corrupting the world's governments, AND still being willing to make personal appearances in order to tempt relative nobodies and gain control of their souls. So what does he want with all those souls? Yeah, he tortures them, but you'd think it would be a tad bit difficult to torture someone with no physical form, and it would have to get boring eventually, right? If he's the evil genius people seem to think he is, sticking pitchforks into people's asses couldn't possibly be particularly intellectually fulfilling for him. Really, the fundamentalist version of Satan HAS to be bored, if he's going out and doing all this stuff on Earth despite getting most of humanity's souls by default.
While there really isn't much detail about the Devil in the Bible itself, popular theology has painted him as God's favorite angel, who was cast out of Heaven when he tried to steal the big guy's throne. But was he simply greedy and power-hungry, or did he honestly want to make some changes in the way things were being done? What with the vengeful, destructive way God is always acting in the Old Testament, I could see a group of angels resorting to rebellion after their polite suggestions were repeatedly shot down by the boss. The Qur'an actually says that Iblis (the Islamic name for Satan) was cast out of Heaven after refusing to bow down to Adam, even though there doesn't seem to have been any particular reason for him to do so.
Once again, the serpent in Genesis is not explicitly referred to as Satan, and was more likely intended to be an actual literal snake (the story about the serpent being forced to crawl on its belly and eat dust as punishment for its transgressions has a definite air of the "how the leopard got his spots" type of fables). He's popularly identified as the Devil, though, which would mean Satan was responsible for bringing wisdom to mankind. Wait, if Satan is the one who tempts people toward evil, yet he was the one who gave them the ability to tell good from evil in the first place...that doesn't quite add up, does it? Or maybe it's just further evidence of his having to take entertainment where he could find it. I think the Gnostics might have been on to something after all.