However, you should also know, that it is much easier to get a lot of effects just by using things that are easily accesible to us:
* exercise or even walk (like 45 mins)
* coffee (obviously, unfortunately doesn't work for me)
* tea, green tea, yerba mate, others (amazing and powerful effects)
* music - trance or classical work really well
* binaural beats - also work exceptionally well, for focus and for creativity, idea generation
* meditation (goes with the one above)
So what I am trying to say, there are a lot of ways how we can boost our intellects. Let's not forget really enjoyable ones like green tea for example.