You could just google for it as a PDF, this one looks good
depends on how much you respect 'intellectual property'.
I read it that way initially, and afterwards bought a copy of the film CHARLY on DVD,
so they made some money out of me that way.
The more recent film Limitless is based on a similar premise.
You might also like "On self delusion and bounded rationality"
which goes in the opposite direction somewhat
I think I actually enjoyed the book more than the DVD, and feel like I have experienced something similar myself,
though obviously not to the same extent. On the upside it's really great when you feel like you are coming to a far deeper
understanding of the world, on the downside it really sucks to watch all you gains disappear and life spirals out of control again.
At the moment it only seems like I can manage 3-6 months of higher functioning / greater performance,
followed by around 12-18 months of exhaustion. I need to find a way to get the 3-6 months to really count for something
to get me through the down cycles in between.
I'm not sure if I would consider Flowers for Algernon great literature in terms of the writing style, or even the plot,
but the big ideas and concepts themselves are important to understand and worth the time invested in reading the book.