How do I open a file as root in TextEdit on Lion?
You can open up a textedit instance as root by entering the full path to the actual executable :

sudo -b "/Applications/Textedit.app/Contents/MacOS/TextEdit"


Once your root instance is open you could browse to the file you need or do this from the command line :

sudo su - root -c "open -e /etc/apache2/httpd.conf"