If your friend isn't local, I'd like to suggest that an interestingly packed package sometimes makes the present. Filling the box with tons of shredded, glittery paper and then making the unpacking of the box a mini-scavenger hunt is always fun. My sister sends me packages with a lot of random small things she gets at thrift stores in her town, and she always includes a note that is sealed and reads "Don't open until you are finished unpacking the box!" The note is always a list of each of the items in the box with a short description of how, when and where she got the item and why it made her think of me. Just that extra tiny measure of thoughtfulness makes me feel much happier.
Another idea is these surprise balls, which I found on notmartha.org (http://www.notmartha.org/tomake/surpriseball.html) when I was looking for things to make for presents this holiday season. I made four giant balls using small crepe paper rolls I bought at the dollar store and filling it full of laffy taffy, jolly ranchers, little stickers and trinkets I had lying around in my craft supply bin, good fortunes from fortune cookies, etc. Everyone I gave them to had so much fun unwrapping them that I would definitely make them again, and in fact went back to the dollar store last night to get more streamers!
Even if you don't send her anything but a nice card, though, I'm sure your friend will appreciate that you are thinking about her.