Question: I'm currently following a tutorial to rig a character.

All goes well until I go to Pose Mode to see if my rig moves (I can do that before or after doing the automatic weight things, it changes nothing).

[![Pose Mode](https://i.stack.imgur.com/3kqsV.png)](https://i.stack.imgur.com/3kqsV.png)

What happens is most strange: I select a bone and press `G`. The usual box with the colour arrows appear, I try to grab and move one of them and it turns into a `><` like that. 

[![Cursor Change](https://i.stack.imgur.com/9h0im.png)](https://i.stack.imgur.com/9h0im.png)

So far I've only seen that whilst scaling in edit mode and it does nothing, same with rotating. 
I verified I do not have any lock on location or rotation for the chosen bone or it's neighbours. I also dont have the `ctrl` + `.` or snap to center turned on, I checked all I could in the manual and here and found nothing.
I've spent the afternoon on this and it's driving me nuts.
I haven't found anywhere on the net anyone who talked about a dead scale `><` cursor dragging and replacing the wheel and grab and scale box.

I am following the free rig the biker tutorial on Digital Tutors and so far so good, I checked everything. I'm nearing nervous breakdown.

Answer: 
Judging from your second screenshot, I'd suppose you've got `Manipulate Center Points` activated. While this is useful on multiple selected objects or bones, when bones are **not** connected, it leads to the behavior you describe in your Question. See the GIF below on how to deactivate this feature:

[![Manipulate Center Points](https://i.stack.imgur.com/e5R3T.gif)](https://i.stack.imgur.com/e5R3T.gif)

The purpose of this feature is to **Translate** objects by using **Rotate** or **Scale** functions. In your case, as the bone is already a child of another bone, Translation channels are automatically locked already. That's why nothing happens.
Try Alt , (Alt-comma) - worked for me. :)

What this does is get you out of 'Manipulate Centre Point' mode:

[![enter image description here](https://i.stack.imgur.com/HD086.png)](https://i.stack.imgur.com/HD086.png)