Think that thank you letters are out of style? By the time your future employer receives the thank-you letter, even if it's the next day, they have already decided if they are going to hire you or not.
To use a thank you letter efficiently and provide a personal touch, give it to your interviewer directly after your interview!
There is a higher chance you will be called back for a second interview if you give your future employer this thank you letter. It's especially effective if the employer can't decide on a candidate. Your thank you letter could give you the edge!