axis lock buttons

[Dean]

Wishing there was a way for an absolute LOCK on certain axis movement  
in a view port. For instance if the viewport was showing in it's two  
screen dimensions possible movement in X and Y directions, for  
movement to happen in a direction in one of those directions there  
would have to be a check box in the direction desired. If a direction  
was unselected, there could be NO movement possible in that direction.  
Reason for this request, I find it difficult sometimes to know if  
something has come out of line and it would be good to have more  
visual confirmation what was what.

Dean