Like many of the members who have posted before me, I like the people here.
I can come here after a stressful day at work, kick my feet up, grab a cup of chocolate milk, and chat away with some of the good friends I've made here. It's a nice environment because you can tell that people simply love spending time with each other. We celebrate each other's victories, and pick each other up when we fall.
That, and writing, of course. I enjoy helping people with their writing, and this is the perfect place to do it. Fanfiction, even though I don't write it myself, is a good starting place for beginning writers. I may harp on it sometimes, but I like seeing where people go with the franchise. I just like being in company with fellow writers.