Two security researchers, Robert Hansen and Tom Stracener, claim that hackers can potentially use different types of gadgets like the ones offered by Google to access someone's personal information. Google distributes gadgets made by other users.
The gadgets can add flair to a users web page but can also open a door for hackers. Google claims they evaluate all applications thoroughly and blacklists any that have malicious code. The problem also exists with other social networking sites.
Google says no "inline" gadgets have been made since November 2007 that can access users account information. Google says in their defense gadgets "provide a convenient way for users to view information collected from around the Web in one place."