(slang, Internet) To bump a particularly old topicthread on the internet or in an electronic forum, by posting an ironic or humorous reply to a previous message.
Wiktionary
Origin of Screwtape
See the C. S. Lewis book, The Screwtape Letters, from the compound of screw + tape. The internet sense is thought to have originated on the internet Flintstones forum, Pebblescrap.