1. My brain needs exercise but I only have time for bite-size chunks.
2. I need a place to rant where doing so won't result in my losing friends (see 7).
3. To remind myself that I can type and even compose sentences.
4. To explore some of the ideas which are interesting to me.
5. It's something new.
6. To exercise my don't-wait-til-it's-perfect muscle.
7. As a verbal-processor I usually need to talk/write my way through things as a way of making sense of the world (see 2).
8. I'm a bit of literal exhibitionist (metaphorically-speaking).