cut -f1 -d" " < ~/.bash_history | sort | uniq -c | sort -nr | head

bash history

my standard user:
  59 ping
  46 ls
  37 su
  36 python
  35 ssh
  29 cd
  26 git
  21 ./createLionUserSetup.py
  20 man
  15 diskutil
local admin:
  11 ls
  10 make
   8 pwd
   8 cd
   6 /bin/sh
   5 sudo
   5 find
   3 which
   3 vim
   3 ping
acdha's: 
 786 git
 193 django-admin.py
  83 fab
  78 mate
  78 cd
  73 ls
  45 workon
  45 ssh
  44 pydoc
  42 gitx

Three years later!

105 git
36 sudo
35 ls
33 ping
26 ssh
24 cd
18 vi
18 autopkg
14 man
13 zip