brew list --unbrewed

Very quick way to find files not installed by homebrew.

Taken from a command by mxcl on the homebrew wiki.

.DS_Store files and bin/brew are ignored.

Library/Homebrew/ARGV+yeast.rb

@@ -89,7 +89,7 @@ Commands:
   install formula ... [--debug|-d] [--interactive|-i] [--ignore-dependencies]
   remove formula ...
   search [regex]
-  list [-v] [formula] ...
+  list [--brewed] [--unbrewed] [formula] ...
   link formula ...
   unlink formula ...
   home formula ...

Library/Homebrew/brew.h.rb

@@ -281,6 +281,17 @@ def warn_about_macports_or_fink
 end
 
 
+def versions_of(keg_name)
+  `ls #{HOMEBREW_CELLAR}/#{keg_name}`.collect { |version| version.strip }.reverse
+end
+
+
+# Taken from the homebrew wiki (http://wiki.github.com/mxcl/homebrew)
+def unbrewed_files
+  `cd #{HOMEBREW_PREFIX}; find bin etc include lib man share -type f \\( ! -iname ".ds_store" ! -iname "brew" \\)`
+end
+
+
 ########################################################## class PrettyListing
 class PrettyListing
   def initialize path

bin/brew

@@ -39,7 +39,9 @@ begin
       end
 
     when 'ls', 'list'
-      if ARGV.named_empty?
+      if ARGV.flag? '--unbrewed'
+        puts unbrewed_files
+      elsif ARGV.named_empty?
         ENV['CLICOLOR']=nil
         exec 'ls', *ARGV.options<<HOMEBREW_CELLAR
       elsif ARGV.verbose? or not $stdout.tty?