My spider plant gave me a surprise flower this morning. It's probably blooming because it is stressed. I keep it in a pretty small pot because I don't want a huge plant, and I often neglect to water it when it's dry. The flower is only about 3/4" across but a new flower is always welcome in the winter.
They say spider plants are good at cleaning the air of pollutants but I'm guessing you would need quite a few to have any significant effect. They're cheerful plants, though, so I guess they help to clean out the mental pollutants as well.