C. S. Lewis' Screwtape Letters are a delightful and much imitated piece, seldom with success. However, Fr. Longenecker of Sanding on My Head has definately caught the witty, incisive and very instructional feeling of Lewis' original with his Gargoyle Code series.
If you haven't been reading it already, do give it a try. Under all the fun, it's very thoughtful lenten reading. And reminds me that we need to make it to confession this week... Nothing makes those demons squirm so.