Where and When of Blogging

I go through fits and starts with my blogging. On rare occasions I've had periods when I believe I have something to say everyday. I have a friend who does say something entertaining almost every day and I find that pretty inspirational. Then there are times when I'm deep into a project and can't seem to think of one little tidbit worth sharing. I know readers of my blog don't expect to learn the secret to publishing success and how to win the lottery against all odds, but I try to say something of some value or at least an interesting read.
So when should one post something? I tend to avoid controversy on this blog so you won't see any great last word on ebook vs traditional, taxing the rich vs the middle class, or even paper or plastic.(I use cloth reusable bags)
I do blog when I have a new work to promote or some other writing milestone, but many days I search the echoing emptiness of my creative cortex and find a blinking cursor on a blank white page. And I've fallen into a habit of blogging about once per week on either Monday or Tuesday whether I have anything wonderfully original to say or not.
During the summer months, I blog from my home computer but soon I'll be back at school. I'd like to blog on my lunch hour from work. But should I? Use of my computer at school is strictly monitored. So I might not.
I'm sure most people who read my blog have their own blog going. How often do you write a new post and when do you do it?