1. A computer-implemented method of maintaining a list of documents of interest to a user within a corpus of documents stored in a database, the method comprising the steps of: creating and storing an association of an editable user document with said corpus of documents; generating an initial list of documents within the corpus based upon an initial content of the editable user document by using a cross-referencing engine to cross-reference said initial content with content of documents in the corpus, each entry in said initial list being assigned a corresponding initial ranking value computed by the cross-referencing engine based upon said cross-referencing; presenting the user with a display of an initial list of one or more documents of interest from within the corpus on the basis of said initial ranking values; responsive to one or more updates of the editable document entered by the user, generating one or more further lists of documents within the corpus based upon updated content of the editable user document by using the cross-referencing engine to cross-reference said updated content with content of documents in the corpus, each entry in said further list being assigned a corresponding revised ranking value based upon said cross-referencing; and presenting the user with a display of a revised list of one or more documents of interest from within the corpus on the basis of said revised ranking values.
2. The method of claim 1 wherein the editable user document is of a type selected from the list comprising: plain text documents; word processing documents; email messages; instant messaging or other interactive chat messages; collaborative documents; Short Message Service (SMS) messages; and web-hosted documents.