Recently I had a scary experience. A disabled veterans organization called offering to pick-up donations from my house. Since I hadn't heard of their name, I asked who they were. I also asked if they were a non-profit. I was utterly shocked to learn that they were not a charity, but a for profit company!
What deceptive fraudulent marketing. Although they claimed they gave a certain percentage to disabled veterans it smelt and felt like a scam.
While looking for new charity's to donate to, I began searching the web, Charity Navigator is a very nice website that looks at a charity's tax filings to determine it's efficiency. For example, do you really feel comfortable giving charity to an organization that spends most of its money on administrative costs?
I examined several charity's through it and found to my dismay that a national cancer charity was very inefficient, giving more money to its operations than to cancer patients.
You might want to check it out.
Also, here's a great article from consumer reports.