Christmas help! Puzzle/cypher for present

[thatdarncat]

I'm getting an engraved ipod for Seri for Christmas, and I need some help with the engraving. I haven't decided exactly what I want it to say, but:

I want it to be something simple.
She loves puzzles and cyphers like you find at "the stone" (www.thestone.com)

I have 2 lines and 27 characters per line to write the message - can anyone suggest a simple cypher or puzzle?

I'm still deciding on the message, but with a cypher it shouldn't matter?

*goes back to writing down ideas*

 

[thatdarncat]

http://home.att.net/~stephen821/cyphers/codesgen.htm

looks useful, a simple substitution cypher with the encoded message on the first line and the key on the second line might work... I'm sure she'll figure it out quickly

 

[Pyrex]

If the cypher is simple enough she may not even need a key, giving you a second line of message.

You could probably go with something straightforward like Rot-13 or atbash.