There is an excellent article about how to answer the salary question on LinkedIn:
Basically treat your salary as confidential information (which, in fact, it is) and refuse to disclose it by saying "I'm not comfortable sharing that information" and only discussing what your salary requirements are for the position for which you are applying/interviewing.
The article goes into a sample conversation where the recruiter is pressing strongly for this information, and the applicant is deflecting the question until he has to answer it directly.
(a partial quote from the article)
IVO: ... I definitely wouldn't be comfortable with [telling you my prior salary]. Like I said, I'm not asking [new employer] to tell me what he pays my prospective co-workers or what he pays the contractors who work for him now. That isn't any of my business, and I feel that my past salary information is confidential too. I'm sure you understand.
CAROL: You're not the first person who's shared that point of view with me, and I do understand. Some of our managers are pretty old-school in that respect. I will pass on the information to Josh and confirm that he wants to do a second interview, and my gut says that he will.
No one is going to overvalue your services, but plenty of people will undervalue them. You have to value them first, and valuing yourself includes knowing when to say "I'm not comfortable with that request."
When you find your voice, your muscles grow. When you cave and cower and pretend that going along with any off-the-wall request or demand is the safe -- and therefore best -- option, your flame will shrink.