I'm sure most Visual Studio users have heard of Carlos, he's the man behind MZTools, one of the most useful Visual Studio AddIns around.  I've been working with it since the vb6 days and have converted most of my colleagues to using it as well.

If your into Visual Studio extensibility then this blog is worth a read - as are his regular forum posts, I've certainly learnt a lot from him in the small amount of work I've done in this area.

The blogs available here as html and the rss is here