Rotation Tool

Galvax

Is there any way to select your axis of rotation with the key board? It would be really convenient if I could just hold x, y, or z while using the rotation tool to select any of the grid axes.

Gaieus

No, but you can pretty easily align the axis of rotation (AOR) to any axis (or in fact any geometry/guide).

Select the object you want to rotate
With the Rotate tool, click on a point that would be on the AOR and keep the left mouse button (LMB) down.
Start dragging the cursor along the axis (or any edge or to another endpoint or along a guide line - you name it) you want to rotate about
NOW release the LMB and see the Rotate tool locked.

Alan Fraser

To rotate about the world axes, you just need to hold the rotate cursor in empty space, roughly facing along the required axis until the cursor turns that colour, then lock it with Shift before applying it to the selected object.
On appropriate models, it's sometimes helpful to make a temporary cube that you can inference off in a similar way. This saves having to zoom out to find some empty space.

jgb

You can set the Axis of rotation to anything you want, but if some other face in the drawing is at that AOR it becomes super easy.

Select the object to rotate.
Select the Rotation tool, but do not click on anything yet.
Position the Rotation tool ON the "remote" AOR face then press and hold the <SHIFT> key.
Move the Rotation tool to the correct position on the selected object and click. Release the <shift> key and complete the rotation.