Spiked Chains also work great on Berserkers, particularly into paragon. The lashing flail feat (requires mc fighter, but pretty much all non-defenders want to mc fighter anyway) adds a slide 1 to flail MBAs, which you can trade via flail expertise to knock the target prone. The dragging flail feat then adds back the slide 1 after you knock something prone with your flail.
At-will slide 1 and prone with reach is very good on a defender, because it means you can drag monsters into your aura and knock them prone, significantly limiting their options (they pretty much have to stand up and attack you, unless they have reach, a teleport, or a death wish), and you can slide monsters away from their target when they do violate your aura, nullifying their attack with your punishment.