@sylvestrekellan,
It is not common fact that all females would like the same type of gift. Its difficult because every person and every woman is different. I would love a scented candle as someone else mentioned, but I have a friend who cannot stand candles. Some women love flowers, others think it a waste of money because it dies so quickly.
It would be better if say it is a woman in the work place that you notice what she likes. If you do see her with a coffee mug in the morning then yes an appropriate mug with say a dog or cat (if you also know she owns a particular pet) would be nice, or with her name or something else. If you know she stops at Starbucks every morning on her way into work then maybe a Starbucks gift card; if she tends to go to a particular deli in the area for lunch often a gift card from there, if she likes some chocolate in the afternoon - pick her up some nice chocolates.
I would do similar for any man in the office. You are not her best friend so the expectation of a "perfect" gift is not the goal - more a small token of something that she may enjoy.