I know, I got a little carried away with the title.
Something I recently realized is that Excel is omnipresent, no matter what your profession or job title is you are bound to use it. When I was thinking about it, I have had to use Excel in all my jobs bar none. I am pretty sure, most other professions will need it too. Excel is used from complex financial modeling to maintaining a simple list of names and email addresses. It can be the tool of choice for a MBA Marketing graduate to a software tester. All professions almost always use it at some point.
Due to this it makes sense to learn important features of Excel that will help you in your field of work . You can also demonstrate this useful skill during the interview and also put it in your resume for future interviews.
The surprising thing is Excel is one of the most powerful and feature rich sofware you will ever come across! It may just look like a screen full of white cells, hard to type in. But boy does it do some cool stuff that you would have never guessed.
If Excel is heavily used in your profession you better become an expert and make sure to put it in your resume prominently. Just like a wanna be bodybuilder wears a t-shirt a little too tight to show off his non-existent bulging biceps. But at least in your case Excel skills in the resume is a welcome sight to the recruiter and the interviewer, unlike the latter.
Head on over to Chandoo to learn more about Excel and its capabilities. I have decided to improve my Excel skills as well. I recently came across this site and the author seems to know what he is talking about.
Learn it and use it!