This is a remix of my customizable heart message (http://www.thingiverse.com/thing:247436/) with the ability to add a loop for a necklace or a charm bracelet.
I made it customizable so you can put in whatever message you want.
In case you don't want to customize, I've uploaded stl's of "I love you" and "My friend"
Customize and print. I used standard setting on Makerware and a Replicator 2.