On Facebook, I've got my real-life friends there but also subscribers which are usually IT people. Can I post something and make it visible only to subscribers and my "IT friends" (a list)? I don't want my regular friends to see technical posts.
To some extent, yes. When writing a post, if you click on the gear icon, you can set custom privacy settings for the post, to include/exclude specific lists and networks.
However, Facebook's About page for the Subscribe Button states:
So you may not be able to explicitly include your Subscribers in this list. (I don't have Subscribers set up; you'll have to try it.)