duplicate lines in ls listing?

I run current, and I sort of expect this behavior I jusrt noticed is an 
artifact of that, so I didn't send this to -questions.  Hope I'm not 
abusing things.

I just noticed some very odd things happening in ls listings.  First 
noticed this in listing /dev, where some files listed twice, even though 
there name seemed to be a total duplicate.  The file I first noticed 
this with was /dev/sndstat.

Later on, as root, I copied a dmesg listing I had saved in root's 
homedir to my "chuckr" dir, then did a chown so that chuckr coud won and 
move it.  I took a look at the file, noticed it was a verbose dmesg when 
I didn't want it to be, so I moved back to the terminal that I was root 
in, and copied a different named dmesg to the same name in ~chuckr, 
again chowning it.  When I went back to the tty that chuckr was logged 
in on, and ls'd the dmesg, I was shocke dto find that there were two 
different lines for the file "dmesg".  Huh.

Anyone could maybe give me a reason for this odd behaviour?  For exrtra 
info, when I hit moount, the line I get for /home (a separate fs) is:

  /dev/da0s2b on /home (ufs, NFS exported, local, soft-updates)

Thanks