Since everyone seems to be doing it:

$ history|awk '{a[$2]++ } END{for(i in a){print a[i] " " i}}'|sort -rn|head
  189 ./bin/redcar
  51 cd
  41 gst
  29 git
  28 irb
  23 less
  21 ruby
  20 gca
  19 ls
  13 sudo

I guess it’s pretty obvious what I’m spending my time on :).