Short of that, if you haven't ever socialized with her before you might want to casually ask her if she'd like to meet sometime for lunch or coffee. Once you've got her out in that kind of environment you'll probably be better able to judge whether she'd be amenable to anything more.
Coffee is the best approach nowadays in the office. Bodie is absolutely correct about using coffee to judge whether she's into you.
I'll never forget the first time I asked a co-worker to Starbucks, we found a couple of the nice, comfy chairs to sit down at and that's when she immediately dropped to her knees before me, unzipped my fly and commenced to give me the grandest co-worker hummer ever:lovecoupl Maybe she needed a little more foam for her latte?:dunno:
I've prefected the coffee approach actually. If there's a chicky I have my eye on, I'll say something like, "I think I'm gonna run out for a coffee. I'm kinda draggin' this afternoon. Want me to bring you back something?" If she says "No" 3 straight times, most likely she wants you to leave her alone. Start with the "bring back approach" then move to the "Hey, you want to hit Starbucks/Whatever"....
The office is a place where CAUTION is the best approach. We all want to bend over our co-workers and bosses over their desks, but that usually results in harrassment lawsuits and firings..:dunno: