This paper presents S-Notebook, a tool that makes it possible to "extend" mobile devices with augmented paper. Paper is used to overcome the physical limitations of mobile devices by offering ad- ditional space to annotate digital files and to easily create relation- ships between them. S-Notebook allows users to link paper annota- tions or drawings to anchors in digital files without having to learn pre-defined pen gestures. The systems stores meta data such as spa- tial or temporal location of anchors in the document as well as the zoom level of the view. Tapping on notes with the digital pen make appear the corresponding documents as displayed when the notes were taken. A given piece of augmented paper can contain notes as- sociated to several documents, possibliy at several locations. The annotation space can thus serve as a simple way to relate various pieces of one or several digital documents between them. When the user shares his notes, the piece of paper becomes a tangible to- ken that virtually contains digital information.