wipe, clean, etc

I have a new laptop that the harddrive is dying on. I have a warranty replacement on the way. I have our company's source code on the drive. I just got the thing to boot (probably for the last time) Is there a simple command I can run to make sure that the data on the drive after I delete the source code dir is completely gone? I'm using reiserfs. B-) P.S. don't know how long it will stay up, so time is of the essance