recover root password

previous post i mentioned about only hp-ux will ask old root password if you want to change the root password. in case you lost the root password, here is a list of a good compilation on how to recover the root password on various flavor of unixes:

Solaris
how do I log into this machine - with a twist... (http://www.unix.com/showthread.php?s=&threadid=1927 )
Lost password on a SPARCstation Voyager (http://www.unix.com/showthread.php?s=&threadid=13702 )
How do I restore the etc/shadow file (http://www.unix.com/showthread.php?s=&threadid=3895 )
Root Password Lost !!! (http://www.unix.com/showthread.php?s=&threadid=9488 )
root locked out (http://www.unix.com/showthread.php?s=&threadid=2492)
sc password (http://www.unix.com/showthread.php?t=22079)

HP-UX
root pwd (http://www.unix.com/showthread.php?s=&threadid=13882)
lost root password using (SAM) trusted security (http://www.unix.com/showthread.php?s=&threadid=2084 )
I lost my password root (http://www.unix.com/showthread.php?s=&threadid=12466 )
passwd file corrupted (http://www.unix.com/showthread.php?t=17175)
Boot interaction ( http://www.unix.com/showthread.php?t=22534 )
Re-enabling a locked root account on Trusted HP-UX (http://www.unix.com/showthread.php?t=25319 )

Linux
root and all but 2 users locked out (http://www.unix.com/showthread.php?s=&threadid=12419 )
root password (http://www.unix.com/showthread.php?s=&threadid=5224)
how to retrieve root paswd ( http://www.unix.com/showthread.php?t=1844)
Help! passwd file corrupted (http://www.unix.com/showthread.php?t=18908)

AIX
root account has been locked (http://www.unix.com/showthread.php?s=&threadid=13658 )
Boot in Single-Mode (http://www.unix.com/showthread.php?t=18760)

Tru64
How to Enable locked root account (http://www.unix.com/showthread.php?s=&threadid=8360 )

SCO
Fortgot root password SCO 5.0. (http://www.unix.com/showthread.php?t=20345)

Ultrix
I neede help!!! (http://www.unix.com/showthread.php?s=&threadid=3208)

NCR Unix
single user mode - user accounts passwords (http://www.unix.com/showthread.php?t=17435)

Windows/XP
Beginners Guides: Forgotten Passwords & Recovery Methods (http://www.unix.com/showthread.php?s=&threadid=16216 )

source: http://www.unix.com/showthread.php?t=14327

ooops, they got for windows as well :)
i think on linux is the easiest one, so make sure you don't lost it :)
or maybe it time to use unix password manager