I've done a few half-hearted obfuscations before. This one will probably only work on Linux. It is very possible that it will only work on the Debian-derived distro I'm using right now. This is a useful script, and I'm regularly using the non-obfuscated version from the command line on my new notebook machine.

      use##########
     DirHandle;#####
     $bd="/proc/a".#
 "cpi/battery";print map{#
/\D+(\d+)$/x&&($d=$1+1);###
open(I,"$_/info");%i=map###
{/^(.+?):\s+(.+)$/x&&($1,##
$2)}<I>;open(S,"$_/state"##
);%s=map{/^(.+?):\s+(.+)$##
/x&&($1,$2)}<S>;$s{"rem".##
"aining capacity"}=~/^(\d##
+)/x&&($r=$1);$i{"last f".#
"ull capacity"}=~/^(\d+)/x#
&&($c=$1);$s=100*($r/$c);##
$i=($s{"charging state"}=~#
/^d/x)?"-":"+";sprintf(####
"%d: %.2f%%%s\n",$d,$s,$i)#
;}grep{-d}map{"$bd/$_"}####
grep{!/^\./}DirHandle->new#
 ($bd)->read();###########
  ######################
[download]

Maybe it's not all that obfuscated, but it's way beyond my personal comfort level :-)

Update: Oh yeah, what it does... It checks the current charge on your battery, and whether your charge is increasing or decreasing.