— command history

history | awk {'print $2'} | sort | uniq -c | sort -k1 -rn | head

example

// brand new netbook
  24 ls
  14 cd
  12 defaults
   9 unzip
   8 ssh
   5 mv
   3 mkdir
   3 chmod
   3 cat
   2 unrar

// quilime.com
 173 git
 140 ls
  84 cd
  18 emacs
  15 cat
  13 mv
  12 rm
   5 ln
   4 mkdir
   4 ./scripts/content