Anytime a disaster occurs such as the earthquake in Haiti, online scams are created to capitalize on the generosity of unwary persons making donations. Spam emails and search engine optimization (SEO) poisoning attacks are common ways that evil is propagated. Spam may contain links to phishing sites which try to capture personal and credit card information. Searching for key words will return search engine results that link to sites full of malware (malicious software). Search engine optimization (SEO) is the technique of using key words on web pages in order to improve search engine ranking and get more hits on a website. Like anything else, SEO can be used for good or evil intentions.
When making donations, be sure to verify the identity of the recipient ministry. Know who you are supporting so that the usefulness of the gift is maximized for the glory of God.
Here is one ministry that I trust which is working in Haiti to help widows and orphans: Vision Forum Ministries.

