Rules to workplace flirting:

1) don't, unless the other party expresses interest.
2) stop immediately if the other party expresses any discomfort.

Rules to behaving like a human:

1) treat everyone with respect.
2) do not treat people disrespectfully.

Easy, isn't it.

No, girls like flirting (just like guys do) on their OWN terms. It has no place in a professional context. At a conference, or at work, I want to be treated like a professional. If you are busy thinking about whether I'm attractive or not, you're not thinking about what I'm saying.