Title says it all just list your top 5:)
@extremis: He is a gun for hire yes. But he has saved lives as well. Not always because he was payed. He has even been cited as a Anti-Hero on more then one site, including this one.
that's because he was once turned into an anti-hero for his own series one time if I'm not mistaken.
But the most notable iteration of him, not to mention the new 52 has him as a villain. Anti-villain maybe, but still a villain.