Thinkgeek.com is one of my absolute favorite silly/quirky places to get things.
If she's has a cellphone... how about a SWAT/ tactical throat mic? After all, it's hard to put ear peices under habits http://www.thinkgeek.com/electronics/cell-phone/c8e1/#tabs
Or if she likes Doctor Who: "The Angels Have the Call Box" tshirt
http://www.thinkgeek.com/tshirts-apparel/womens/e78e/
Who doesn't need a hand painted silk bacon scarf?
http://www.thinkgeek.com/tshirts-apparel/miscellaneous/e64f/
Nightvision goggles, caffeine molecule necklace, lightsaber umbrella, titanium spork, Mad Scientist Wooden Blocks (A - Appendages, B-
Bioengineering, C - Caffeine, D - Dirigible, E - Experiment, F - Freeze ray, G - Goggles, H - Henchmen, I - Invention), giant plush microbe, swiss army knife w/ flash drive...
And then (thinkgeek aside) there's just fun stuff related to interests:
- Tapshoes or a Broadway Show or Cirque du Soleil tickets (depending on whether she like seeing or doing)
- An airplane or helicopter ride
- National Geographic Genographic Project (to trace genetic history) http://www.ngsednet.org/community/index.cfm?community_id=278
- or their "every page of every issue of National Geographic for the past 121 years on 6 DVDs http://shop.nationalgeographic.com/ngs/browse/productDeta...
- A kindle or Nook, with some prebought Dr Seuss or Shel Silverstein
- Midnight catechism (this REALLY depends on her sense of humor, I went for the first time my mass twice a day grandmother, her priest, and two nuns, and several women from their church... but it's... ahh... tongue in cheek http://www.youtube.com/watch?v=7Jrh_uuPmd0 Funds from the tickets go toward helping retired nuns in need)
Essentially an experiential present for something she loves doing; culture, adventure, music, reading, mad scientists, bacon...