I agree with that [MENTION=362748]SquidPuppet[/MENTION]. I run an internal Analytical Services business at the company I work for (I'm a chemist on the characterization/QC side), and get some really stupid questions that aren't directly linked to a sale all the time. I'm at a small company so my plate is always overflowing with work as well.

I've developed some canned responses and references, contacts and collaborators within the industry that I can quickly refer people to, so fortunately I can still deal with them in a polite and timely manner. "I wish you luck in your analysis" is something I end a lot of dumb inquiries with .

Still, if you can be polite and take a little time to educate a customer, it can result in some references, trust in your expertise or even direct sales down the road.