Nootropics.

Some authors, especially in the transhumanist movement, have suggested the use of "smart drugs", also known as nootropics, as "motivation-enhancers". The effects of many of these drugs on the brain are not well understood, and their legal status often makes open experimentation difficult. It is a fact that some of history's most productive artists have also been drug users, although it is not clear whether this correlation is also of a causative nature, or if so, which is the direction of causation.
Converging neurobiological evidence also supports the idea that addictive drugs such as cocaine, nicotine, alcohol, and heroin act on brain systems underlying motivation for natural rewards, such as the mesolimbic dopamine system. Normally, these brain systems serve to guide us toward fitness-enhancing rewards (food, water, sex, etc.), but they can be co-opted by repeated use of drugs of abuse, causing addicts to excessively pursue drug rewards. Therefore, drugs can hijack brain systems underlying other motivations, causing the almost singular pursuit of drugs characteristic of addiction.