Computer Whiz (Fallout 3)

Computer Whiz is a Fallout 3 Perk.
 * Requirements: Level 18, Intelligence 7, Science 70%
 * Ranks: 1
 * Benefit: Fail a hack attempt and get locked out of a computer? Not if you’re a Computer Whiz! With this perk, you can attempt to re-hack any computer you were previously locked out of.

Commentary
You could, of course, quick save before hacking and quick load if you fail.

Even more easily, you could power the terminal off before using up your last attempt, then try again.