[nl]

Just use ROT13 - same space requirements as in plaintext

(I really, really hope people realize that is a joke. Otherwise this might be the worst piece of advice I have ever given on the internet)

[jowiar]

One iteration of ROT13 is too fast to compute to guarantee any sort of security. If you really want to secure your passwords, make sure you perform 2↑↑100 iterations of ROT13 or so to ensure substantial computational cost to the operation.

[dhimes]

Yeah- you need at least rot26 or else it's just too easy to crack with today's technology. But everybody ought to know that. (Hey! It's April 1st somewhere...um, or will be in a few hours)

[acheron]

Fortunately I've already upgraded my encryption to rot52.