I think GiveWell is a good starting point: http://www.givewell.org/giving101
Though there's a lot more to say: https://80000hours.org/2015/12/where-should-you-donate-to-ha...
Yay for Bill Gates! What a great guy!
Using the superman example: despite Superman's obvious aptitude and passion for fighting crime the author would prefer he spend his time turning a crank to make more money to donate to crime fighting efforts. I think that is terrible advice. Further, while SMBC is trying to be satirical (and succeeding I think), the author of the article crops the comic hiding the personal cost to Superman the comic expresses in later panels. And then to get REALLY nerdy with it, if Superman isn't fighting crime in the DC universe, no amount of free energy would matter because Darkseid or Lex Luthor or somebody else only Superman could stop would probably have either conquered or destroyed the earth.
My life has recently been impacted multiple times by talented doctors and nurses who could certainly have done something more profitable with their skills and so I am perhaps reacting more emotionally to this article than is necessary. But telling people not to be doctors and nurses and instead pursue something more profitable because "Money is better than doing good things yourself!" Sounds like the kind of bullshit Lex Luthor tells himself as he vaporizes a small city to ransom Superman into letting him be President.
Choose between those two options based on which you'd be best at and the needs of the problems you want to focus on.
Earning to give is a way the wealthy ease their conscience (not unlike carbon offsets). It is not good advice to give people with the heart, courage, and strength to be one of those front line warriors at a non-profit or in social work and to claim otherwise is garbage.
Nobody makes a bigger difference to the children and families who experience birth defects or childhood illness than the nurse in the children's hospital. Certainly not the rich goon who contributed the most money and got it named after him/her. Without that rich goon, a need would still be fulfilled by people whose lives were effected by the lack of such a facility coming together and pooling their resources to make it happen (the whole point of government, taxes, and society in the first place).
Without that nurse, there's nobody to take care of those children post surgery and offer the love, support, and attentive care that only someone with that kind of courage and compassion can provide.
No one says your mind and talents must be constrained to your job forever, but if you can do it you should.
Superman DID run vaccines to people in ADDITION to saving the world from more petty (and also much more catastrophic) crime. So the example (which in the comic is hilarious and presented ironically) the article sets itself on is a false choice.