If your habit is what I think it is, I have the opposite habit - I never use sudo until it tells me I've tried to do something I'm not allowed to do - even if I know it's not going to let me. Then I use "sudo !!"

> Then I use "sudo !!"

Wow. For six years I've been doing "UP + CTRL^A + sudo + SPACE" instead. This is much better.

Off-topic:

I use Ctrl-P Ctrl-A sudo <space> which is exactly the same number of keystrokes as "sudo !!" and a much more general solution in my opinion.