All of 'em! If I have access, I have root. Just "sudo bash" and onward and upward!
-Edit
This is at my new job. A huge mixed environment of Solaris 8 and 10 and RHEL and SLES 9. I am in the build team though and am not supposed to access production servers. This does not mean that I cannot and as a result, have access to over 5000 servers globally.
At my older job, I was in production support and had root access to over 200 Solaris 8, 9 and 10 servers.