I scored high on both (4.5 openness and 4.2 conscientiousness), so, err... good question!
(AKA I really, really wish I had an answer for this.)
In the few minutes I had before posting this, I managed to scare up this 2003 meta-analysis that tried to correlate the big-five with Holland's RIASEC occupational types. Before reading I was expecting to see (85%) a correlation between conscientiousness and artistic/openness and artistic, with the prior that I attending an art school and successful art seems to hang on both qualities.
http://www.ibrarian.net/navon/paper/PERSONNEL_PSYCHOLOGY_2003_56.pdf?paperid=20534921
Spoilers: I was wrong. The analysis concludes that openness correlates with Artistic and Investigative types (Table 5) and, of those, conscientiousness correlates very weakly to Investigative (Table 3).
Heading to Wikipedia, you can find sample careers for RIASEC codes below, but I'm not getting a sense that many of these careers really combo well with conscientiousness and openness.
http://en.wikipedia.org/wiki/Holland_Codes
Noted exceptions: Technical writer, "Counselor", Psychology/Psychologist
Of interest: https://www.psychologytoday.com/blog/beautiful-minds/201108/is-conscientiousness-compatible-creativity
(I can't say I'm really a fan of the big 5 questionnaire in general, though. Agreeableness mixes together kindness and conformity. Conscientiousness mixes together industriousness, dependability and extrinsic motivatability. Openness confounds sensation seeking and open-mindedness. I know it's the most respected assessment, but I think it's really messy.)
In 2011, InquilineKea posted a Discussion topic on YourMorals.org, a psychology research website which provides scores of psychology scales/inventories/surveys/tests to the general public to gather large samples. Niftily, YourMorals lets users sign up for particular groups, and then when you take tests, you can see your own results alongside group averages of liberals/conservatives/libertarians & $GROUP. A lot of time has passed and I think most LWers don't know about it, so I'm reposting so people can use it.
The regular research has had interesting results like showing a distinct pattern of cognitive traits and values associated with libertarian politics, but there's no reason one can't use it for investigating LWers in more detail; for example, going through the results, "we can see that many of us consider purity/respect to be far less morally significant than most", and we collectively seem to have Conscientiousness issues. (I also drew on it recently for a gay marriage comment.) If there were more data, it might be interesting to look at the results and see where LWers diverge the most from libertarians (the mainstream group we seem most psychologically similar to), but unfortunately for a lot of the tests, there's too little to bother with (LW n<10). Maybe more people could take it.
You can sign up using http://www.yourmorals.org/setgraphgroup.php?grp=623d5410f705f6a1f92c83565a3cfffc
All quizzes: http://www.yourmorals.org/all_morality_values_quizzes.php
Big 5: http://www.yourmorals.org/bigfive_process.php
(You can see some of my results at http://www.gwern.net/Links#profile )