GiveWell is a nonprofit charity evaluator, which does research on the effectiveness of different charities. They promote charities which are transparent about what they spend their money on, have evidence that it actually makes a difference, and have the means to put extra money to good use.
For example, at the moment their recommendation to donors is to put 100% of their donation to Against Malaria Foundation.
Against Malaria Foundation is a great example of how GiveWell's charities are different from your standard opaque mega-charity. All donations used exclusively to buy mosquito nets at $2.50 per net. Individual donations are used for a distribution to a particular area, and they take photos, videos and surveys to prove that the nets are actually being used and making a difference. They also email you regularly to let you know the progress of the nets that you paid for. GiveWell also provides a calculation of cost per life saved - for example, this calculation shows Against Malaria Foundation has an estimated median cost per death avoided of $5469, and median cost per under-5 death avoided of $6911.
For those who are poor as shit don't feel like donating, you can register Against Malaria Foundation (or another top charity) with Amazon Smile so that 0.5% of your amazon purchases go to them. $50 of Amazon shopping = one net!