28. A method as recited in claim 27, further comprising a step of specifying the query formulation at least partially in terms of query attributes and of values for said query attributes.
27. A method of specifying a hyperlink, comprising the following steps: embedding a query formulation in the hyperlink; embedding one or more executable rules in the hyperlink, wherein an individual executable rule, when executed, performs the following steps: examining a list of attributes on an individual computer; adding a search predicate to the query formulation depending on the values of the attributes.