There's tons of interesting studies about rs4680 (http://www.snpedia.com/index.php/Rs4680). Although I think all the data is still to broad to make any conclusions.
I think I might give modafinil a go just to see what happens.
Modafinil improved the cognitive performance of Val/Val's (G,G)s across most of the tests (memory tests, mood tests, "Vigor" tests, reaction rate tests, well-being, fatigue, are ones i remember). Met/Met's (A,A)s did not see any statistically significant improvement on most of the tests. One test where there was a small effect for Met/Met's was in subjective well-being.
The study also looked at sleep recovery after the prolonged wakefulness. All participants entered deep sleep faster than normal.
90% of Val/Val's correctly identified their group (placebo vs. drug). 66% of Met/Met's correctly identified their group.
There were 10 people in the Val/Val group and 12 in the Met/Met group. But the small number of participants should be accounted for in the p-tests, as far as I know.
However, like you, I'd still try it given the chance. Regardless, lets hear it for our naturally increased dopamine!
Has everyone on HN gone crazy for the day or something?
I'm seein' robots.