Originally Posted by captainkudzu
A walk-in should not include your cover letter. The person walking in could write an introduction letter (or you write it and he signs it).
I disagree (respectfully)... you should submit your materials to HR in the same manner when your items are being walked in as if you were cold mailing or submitting in some other form. The only difference is that on top of your cover letter there should be a letter of recommendation from the person walking your resume in introducing your application materials.
The recommendation states why the company should hire you and how your referral knows you. The cover letter introduces you and expands on your resume.