[Heather]

Congrats to your friend!
Only initiated members can wear the crest, but letters are fine.
Let's see... owls are always great, as are pictures albums b/c I have tons of XO pics (I actually found one one time that was red and yellow). I really like my Chi O key chains and my mousepad (I actually had to buy that one for myself). I'm sure she'll be getting a lot of the typical stuff during big/lil sis week. If you are looking for something "really nice" maybe something engraved with the letters. (Like a jewelry box, or a pic frame for her to but a bid day pic in.)

If you are greek, (I couldn't remember from your post) you could make a pic frame with XO on one side and your sorority on the other, then get a pic of you two in your letters. (show the panhellenic spirit there!) I have a Chi O sister who's real sister was a ZTA. They got matching (same fabric and design) letter shirts, very cute!