Seems like stackoverflow.com and other Q&A sites are down.
The following is displayed:
Stack Overflow is currently offline for maintenance
But is it really just maintenance or is it an outage?
This question is unlikely to help any future visitors; it is only relevant to a small geographic area, a specific moment in time, or an extraordinarily narrow situation that is not generally applicable to the worldwide audience of the internet. For help making this question more broadly applicable, visit the help center. If this question can be reworded to fit the rules in the help center, please edit the question.
From the @StackStatus twitter feed:
The StackOverflow Pingdom page is showing the downtime too.