Make sure you choose a cover letter format that you feel most comfortable with. It should be something that could best express your personality but keeping it as formal as possible. Be wary of the details of the cover letter format. It must be clean and neat. It should provide the data directly. There is no need to be colorful or playful with the fonts.
In reality, there are just some people who have developed this mania over grabbing hold of the most unique cover letter format they can find. They think that they will need all the research that can ensure their application letter achieves a desirable look. They feel that if it is not attractive or interesting enough, their cover letter format will end up being thrown in the trash bin.