Unless you want to spend several months a year of your life auditing inefficient "charity" organizations and trying to make judgments about whether they're doing it right and spending your dollars wisely...and hey if you think you're good at that you should probably start your own charity. But if you do, everyone will expect you to work for free. It's a viscous circle.
Donate your time, you'll meet people too.
Unless you're a multi-billionaire, then start a foundation and direct where the money goes.