Maybe I've misunderstood (it wouldn't be the first time) but in your comment you confirmed which site you wanted to be linked to as:
"@rene stackexchange.com – Jason Hutchinson yesterday"
We already have links to this site:
The dropdown button which accesses the "log out", "current community" (etc) is itself a link to stackexchange.com.
Admittedly you need to right click and open in new tab, but that's no harder than clicking the dropdown and navigating to the link within the drop down you are requesting is added.
Depending on where you are on the Stack sites, the first link in the drop down menu is also a link to stackexchange.com.
The "Hot Network Questions" title on the right sidebar is a link to the page you seem to require.
So a little scroll down and it's right there.
Wanting more than those 3 potentials, surely a bookmark is fine?
In a decently organised file/folder setup, it takes less than 5 seconds to hit a book mark.
Have a bookmark folder named "Stack", with all your favourite Stack sites/locations in there.
For the small number of users who may use this, and given the current options, even bookmarks, I just don't think the additional space taken up is worthwhile, and dev time, mobile setup/testing, etc.