My Debian unstable desktop:
dominic@tungsten:~$ history | awk '{print $2}' | sort | uniq -c | sort -rg | head -n 10
    101 ls
     85 cd
     28 svn
     25 sudo
     25 man
     21 ssh
     15 less
     14 mplayer
     12 apt-cache
     11 cat

My Debian stable machine on the net for IRC etc:
dominic@bluebottle:~$ history | awk '{print $2}' | sort | uniq -c | sort -rg | head -n 10
    263 screen
    129 less
     15 ls
     11 links
     10 telnet
     10 grep
      9 cd
      7 ln
      5 ps
      5 cat

Debian stable machine from work:
dominic@iocaste:~$ history | awk '{print $2}' | sort | uniq -c | sort -rg | head -n 10
    112 sudo
    108 ls
     64 cd
     31 cat
     18 telnet
     18 less
     17 nano
     13 dig
     10 man
     10 grep

A Debian stable machine that I work on a lot:
dominic@rep3:~$ history | awk '{print $2}' | sort | uniq -c | sort -rg | head -n 10
    159 ls
     99 sudo
     66 cd
     32 ps
     22 svn
     14 nano
     12 rm
      9 zcat
      9 less
      9 cat