I'm sad that you're losing her and I don't know either of you. 15 years of loyal caring devoted service is so rare in this day and age.

You don't know of anything in particular she wants/needs right now, do you?

If there is something useful she's hankering for you could go that route. I think the framed pic is a must (make sure it is one where she looks great, we hate dreadful pics of ourselves and we DO hide them.) If she's religious a Bible is a good idea, you can get them imprinted with her name on the front in gold.

Something really special and personal, definitely, and a nicely framed pic will suffice in that category. I'd add something useful as well...and money is always useful. She may also be craving a mouse, a new cellphone, a remote control, a small dvd player, heck maybe a car battery, maybe she's mentioned something she really wants or needs?