People have been posting in their blogs about what command they run, based on their shell histories. The command that I've seen looks like this:

history|awk '{a[$2]++} END{for(i in a){ 
printf "%5dt%s n",a[i],i}}'|sort -rn|head

That works, of course, but who wants to use awk and the shell? I pulled out the old Data::Hash::Totals module I wrote a while back, along with Perl's built-in awk simulation:

$ history | perl -MData::Hash::Totals -ane'$x{$F[1]}++;' 
-e'END{print as_table(%x, comma => 1)}' | head
207 vim
143 svn
125 make
90 ack
77 cd
45 sdvx
34 ssq
31 ls
25 ./login-fixup
19 tail
alester:~ : cat `which sdvx`
#!/bin/sh
svn diff -x -w $* | view -
and ssq is just an alias for svn status -q.