Powertoys provides a very useful "Command prompt here" option for Explorer, and I got fed up with selecting this and then typing sh. Here is how you can avoid doing the same and provide yourself with a useful shortcut.
1) Add these lines to your environ.ksh or equivalent.
if [ ! -z $StartupDir ] then cd $StartupDir fi
2) Add the following registry keys.
[HKEY_CLASSES_ROOT\Directory\shell\Sh] @="&Shell Prompt" [HKEY_CLASSES_ROOT\Directory\shell\Sh\command] @="sh -c \"export StartupDir='%1'; sh -L\""
Alternatively run this .reg file to set the keys for you, either run it from the web page or save it as a file with a .reg extension and then run it.