Many years ago Wendy McCarthy told me that in her youth typing or shorthand were skills to which an ambitious young woman should never admit having mastered. This was good advice and it ensured that I remained a purely non-administrative resource and never had to serve coffee as part of my duties.
One skill I have learned to deny is any facility in supporting any technology like PCs or photocopiers. I confess to complete ignorance of such technology - otherwise you end up helping anyone who can't be bothered to RTFM. What is really interesting is that this confession soon becomes reality given how quickly the technology evolves.
Heed this advice. I have learned the hard way in my career that marketing supplemental administrative skills along with your technical skills will do little but place you firmly in the "administrative" bracket. If they think you can do a secretary's work, chances are that's what you'll end up doing. I wouldn't be too surprised if women in particular fall prey to this.