I came across Barry Moltz' article 6 Ways To Let People Pick Your Brain Without Wasting Your Time and thought it had some good advice for experts - particularly those worried about being overwhelmed when they become known as experts. Even if "expertise location" isn't top of mind these days, it's still a valid concern for people who are expected to interact via internal social media efforts.
The question I dread the most from business people is “Can I pick your brain?” While I believe in helping others and paying it forward, I am not even sure how this expression got started since it is so visually unappealing. Why would I want someone to literally look inside my brain and take whatever they want? Sounds like the first ever “business horror” flick!
His six ideas are all about both protecting your own time (as the expert), as well as being helpful as possible. He starts with the most obvious question: are you going to be paid for this advice? Then there are much more practical aspects: get a clear explanation of how you can be helpful; stick with the phone instead of in-person; and then set limits around the time and energy you wish to put into the interaction.
An element I would add would be to find ways to push the request out to "the public" - whether that is on the public web or on the intranet. Post the question to your status feed. Post the answer to a blog or wiki other permanent location, so the next person who asks can be redirected there. Point the person to other likely sources of assistance, if you aren't available (or interested).
[Photo: "title" by elliottzone]