If you are a fellow Photoshop user, and have experienced an unexplained loss of accessing the Hand tool using the spacebar keyboard shortcut, this may have been caused if you are running password manager software 1Password and have used the “Hide” menu option.
I would have never found this had it not been for the warning on TextExpander‘s menubar icon, and the resulting blog post they published regarding TextExpander and Secure Input.
Quitting 1Password and relaunching it fixed the issue for me, so I can only assume it was indeed the culprit.
A tweet from 1Password reveals the specific circumstances under which this will happen, if you are running version 4 of 1Password:
@gcoghill There was a known issue in v3, but it should only happen if your input focus is in the Master Password input field in v4.
— 1Password (@1Password) February 9, 2014
and more details if you are running version 3:
@gcoghill Details if you’re still using v3: http://t.co/VK1topPFL2
— 1Password (@1Password) February 9, 2014