At their best teacher blogs are full of information and idea sharing that benefits other teachers. For teachers of computer science or computer programming one of the most useful things teachers do is to share projects. A good project engages students while at the same time enforcing important concepts that have been covered in class. A prime example of this is a recent post by Mr. Higgins (aka Higgy).
In this post he lists out and describes the projects he is using with his Advanced Placement Computer Science A course (APCS A). The list includes some fairly basic and perhaps familiar projects like ASCII and number base conversion up to some more complex and new (at least to me) projects like a Galton Board. For some he has links to more complete descriptions that I think many teachers will find extreamly helpful.
All in all this is one of the most useful CS teacher blog posts I've run into in a while.