47. Alfred Pennyworth - 300 points
Introduced by Bill Finger, Bob Kane and Jerry Robinson, Alfred initially was a rotund goofy little man. He eventually became thin (to tie in with the Batman film serial of the time).
Up until the 1980s, though, Alfred was someone that did not come into Bruce Wayne's life until much later. It was first the Super Powers cartoon but then most notably Frank Miller's Year One that changed this, and it was Miller who established Alfred's new sarcastic wit, which Miller patterned after the butler in the film Arthur. Up until this point, Alfred was very much just the loyal servant, offering criticism only when asked. Now he served as a dissenting voice to Batman's crusade. His role as Batman's field doctor also expanded.
In his last regular issue of Batman (before moving on to Batman and Robin and then Batman Incorporated), Grant Morrison has Alfred explain his role in the life of Batman beautifully...
He's definitely a unique supporting character.
46. Spoiler/Batgirl (Stephanie Brown) - 306 points (6 first place votes)
Stephanie Brown was introduced by Chuck Dixon, Tom Lyle and Scott Hanna in a clever story where we learn that the daughter of the villain Cluemaster (basically a second-rate Riddler) is intentionally trying to screw up his plans by leaving clues for Batman and Robin to stop him...
She seemed destined for just a clever one-off character until Robin got his own series and Dixon decided to bring her back as a ally/foil. Her guest appearance went over really well and fans clamored for more. She was a breath of fresh air - someone who was a vigilante because she just legitimately LIKED it (while initially it was just to get revenge on her dad, she quickly moved past that).
The problem was that Batman never quite trusted her. She slowly became friends with the other Bat-heroes, though. Finally, she seemed to get her chance when her boyfriend, Tim Drake, had to quit being Robin for a while. She tried to get the job and Batman seemed to say yes, but after less than three issues as Robin, Batman fired her. As it turned out, it was just all a plan by Batman to make Tim jealous enough to become Robin again. One of the dickier moves by Batman, and that guy is ALL about dick moves.
The problem was, Stephanie then tried to prove herself to Batman by implementing a "War Game" she discovered that he had written that would result with Batman taking control of all of Gotham's gangs. The problem was that the inexperienced Stephanie did not realize that the plan she implemented was incomplete (it required Matches Malone, Batman's fake gang identity, to work properly and since Batman didn't know she was implementing it, Matches was nowhere to be seen). In the end, she paid the price for her screw-up by being murdered by the crime boss, Black Mask. Later we learned that her death had been faked by Dr. Leslie Thompkins.
After first returning as Spoiler, she upgraded to Batgirl when her friend, Cassandra Cain, gave up the identity after Bruce Wayne's seeming death. Stephanie excelled as Batgirl, even finding acceptance from Bruce Wayne (after he returned from the "dead") that she was never able to get before. Here she is in one of her very last appearances as Batgirl (it was written before the new 52 but was published after the new 52)...
She was introduced into the New 52 recently as Spoiler again.
45. Lois Lane - 307 points (4 first place votes)
Created by Jerry Siegel and Joe Shuster, Lois Lane is the ultimate in the badass take-no-prisoners, leap-before-you-look reporter trope, making her more than a match for Superman as both a friend and a possible lover.
I think John Byrne captured her spirit well in Man of Steel #4...
and after the party is taken over by terrorists...
The sight of Lois slinging a machine gun dressed in a man's suitjacket because she wouldn't be indebted to anyone is, well, pretty darn awesome. That is how great Lois Lane is. Mark Waid had an awesome panel in Superman: Birthright that captured how some of the things that make her great also sometimes make her difficult to be around...
44. Spectre (Jim Corrigan) - 310 points (7 first place votes)
Jim Corrigan, the Spectre, first appeared in More Fun Comics #51, created by created by Jerry Siegel and Bernard Baily.
Corrigan was a cop who was murdered, then refused entry into heaven, and instead became the host body for the Spirit of Vengeance, the Spectre.
The Spectre is essentially a super-powerful ghost who gets vengeance upon bad guys.
Corrigan was the host for the Spectre for decades.
Perhaps his most acclaimed run was during John Ostrander and Tom Mandrake's series.
Here is a snippet, where they cleverly set the Spectre upon a prison...
While the Spectre acts tough, he can't help but be swayed by the prisoner's plea, leading to a brilliant sequence later in the issue...
At the end of their run, Corrigan was finally admitted into heaven.
In the New 52, Corrigan is the Spectre once again, although there is a different take on the character. Now it is that it is ALL in his mind - that there is no one guiding his justice but himself!