Anyone who has always wanted to write a novel should consider doing National Novel Writing Month (http://www.nanowrimo.org/). I did it last year, and even though my novel was pretty terrible I still had fun and learned a lot from writing it.
I'll definitely do it again sometime, when I have more free time. (It does consume a lot of time. If you've got a startup, you don't have time to spare.)
I have several freind who do NaNoWriMo every year and say it is simply wonderful.