I have the scantest, dimmest personal memories of flannelgraph: probably from some Vacation Bible School experience. To review, flannelgraph is a visual aid for teaching Bible and other lessons using printed felt cutouts that stick to a cloth frame. Gentle and simple and still around, it seems, in some quarters. (You can buy flannelgraph figures at the Adventist super-store up in Silver Spring, Maryland while you're there to pick up vegetarian foodstuffs.)
Swap a whiteboard and cut out print-outs for the felt, and tech topics for Bible lessons and you may see why I'm fond of the videos from Common Craft. They're visually simple, short and on-message. Like their "RSS in Plain English" video, which takes about three minutes to get the concept and application of news feeds. (PeaceBang, this is for you.)
I have to think there's a lesson for church people.
Or you can enjoy this sweetly silly video using real flannelgraph figures "Jesus on Safety"