Writing Laps is where writers write together. It's a favorite.
Most weeks I come with a theme to inspire; sometimes, if I detect a particular mood, I pull from my overflowing supply of ideas. Over 60 minutes, I present 2 - 4 different prompts, and we write (like crazy) during short, timed sessions. With no time to edit or revise, you'll produce lots of imperfect, but amazingly thoughtful and soulful writing. PLUS, I do my best to leave time for some sharing, support and applause.
Note that there are several options: come for a single session or take a monthly or seasonal subscription.