Sadly, I realized this when I started smoking. When I go smoke outside and come back, I can solve the problem I was working on much faster. Cigarette does have some benefits... sad but true.
Back in school we used to call them "Think Sticks" in spite of those that called them "Cancer Sticks". In reality I guess they are both, as nicotine does have proven cognitive benefits.
That was/is the hardest part of quitting smoking (I still smoke very rarely) for me. I just really enjoy stepping outside for a smoke be it from work or at a crowded party. Its just something I like to do I just wish I could find something to replace the cigarette part with.