If you die you keep all your passwords in your head. What Death Switch does is release your passwords at a certain point. It will prompt you for a password on regular intervals. When you fail to enter the password in at a certain point, the software will assume you are dead and email your passwords out to those who you have specified.

With a free Death Switch account you can specify one email to be sent to. Other premium services allow you to add attachments let you sending messages out from beyond the grave.

Death Switch sells themself as sort of an information insurance making sure that those who need it can get your passwords when you’re gone.

Alternatives to Death Switch
There are other better ways to make sure your passwords get out when you die. Try keeping a list of accounts and passwords inside of a fireproof safe and make sure that your loved ones know about the key.