Is there a physics-, chemistry-, biology- or maybe mathematics-oriented Stack Exchange site?
Here are some examples from the overview of Stack Exchange sites:
There may be others as well. Check out the full list of sites for an up-to-date list.
To update the existing answers for SE 2.0, Stacks in scientific fields now include:
If you want to know something about scientific processes like teaching, paper writing / reviewing, ethics, ... then you might want to have a look at academia.stackexchange.com