A weekly or even fortnightly writing group thread would be HUGELY good. Not only on an individual level, but also on a community level.
I'll echo the idea of "bad writing" being the goal. It's easy for everyone to get caught up in the big issue of "Is this good enough?" Vs "Am I having fun?"
I might actually make this my own weekly thing. Give me a bit and I'll make my own post on this.