I use a blogs, but not exactly the way Josh K is talking about.
First, I have my scratch pad / generic thoughts that come to mind while going about my day. I'll fire off an email to this blog from my phone to keep that thought in storage, go back later, and look at all the small ideas I've had. Here's a snapshot of some things recently submitted (the blog is non-public):
negative code : I took my 300 lines and reduced them to about 60, with a object decliration that actually allows 10x greater versitility.
stuxnet: write something about the virus controlling facilities, net neutrality, the conspiracy, the bullocks
code igniter, drupal, etc..., yii, git
I'm not worried about AI taking over the world because of shampoo bottles, later, rinse, goto 10.
...As you can see, a lot of it sounds like inane prattle, but they all remind me of something I found interesting and I can talk about it at length in a second public blog.
I spend a lot of time writing a few articles about anything any everything. Most of them aren't released public as I don't feel they're suitable for public viewing yet (I like to write a lot of inner-monologue; reflective). But some things I do push out there. Sometimes it's technical, some times it's just neat things you can do with non-digital things, some times I talk about building a better mousetrap for any given programming problem... anything that's interesting enough for me to want to write about. I only have 3 public posts, but there's a wealth of knowledge for myself that I feel I have to edit before releasing.
Things I talk about in this blog:
DIY CD wallet for your car
The off buttons on computers need to be designed like nuclear launch switches (key, cover, toggle switches, push button).
Lastly, I have a non-technical blog. It's good to keep one of these too, it keeps your perspective and communication skills sharp. I normally write things like letters to the local news paper, or politically motivated things, issues about education, social rights, etc... In this blog I've talked about
Value attribution, lack of standardization and bias of education
Transparency of Government data
Letter of rage to my local news station for suggesting house-hold WIFI causes illness.