Installing Slackware in an encrypted LVM

Introduction

When a laptop is lost or stolen (or it may be a desktop computer, but this is more likely to happen with a computer that we carry around), at first we may resent the price of the machine itself (and the personal data on the machine if you do not back-up frequently, which you really should, specially if you move your computer around a lot), until we realize that whomever is in possession of the computer posses access to all of our information: our photos, our documents, our media, all of our browser history, and, to make things worst, he/she may have access to sensitive information such as our credit card and log in information of the websites that we visit. If this lost computer used to belong to a corporate user, things are even worst, as whoever took possession of the computer may have obtain sensitive information about the company or about the clients of the company.