I wonder how many of you might be knowing this fact that Google doesn’t Index the "@" Symbol. Given the rise of Twitter So why doesn’t Google index this symbol to make it easier for us to find all references?
Now According to Matt Cutts, the reason for not indexing the @ symbol was intentional. Why because, if Google did index the "@" sign then the email addresses would come through and it would just make all the spammers to gather even more email addresses for their Spam campaigns. However, Matt also indicated that this may change in the future. You can find Matt explaining the same in this video.