This paper presents the Old English Concordancer (OEC), a new tool to process an annotated corpus of Old English, which goes beyond the prototypical operations of similar programmes (lists, indexes, concordances, statistical information, queries, etc). Since annotation includes also lemmatisation and tagging, OEC can perform all those tasks not only with words but also with lemmas, and can solve any morphological query successfully, regardless of its complexity, by means of Boolean filters. It allows some simple syntactical research at sentence level as well, as it is sensitive to context and word-order. Moreover, the statistical information that the OEC generates includes absolute and relative values of items, as well as their distribution by words, lemmas, class and/or accidence [inflection], vocabulary profiles, etc. The OEC has been applied to an annotated version of The Old English Apollonius of Tyre, and some of the results that can be obtained are presented, along with others that can be indirectly derived from them.