A script that allows you to creates smart playlists, using various criteria to match track attributes (available matchers are regex, timestamp and time-delta).

Get it from http://github.com/sdelafond/mpd/blob/master/mpdspl.py

Usage: mpdspl.py [options]

Playlist ruleset:
       Each ruleset is made of several rules, separated by commas.
       Each rule is made of a keyword, an operator, a value to match
       surrounded by delimiters, and several optional flags influencing the
       match.
       There are 3 types of rules, each defined by a specific delimiter:

         '@' ->  Match according to a timestamp, for instance:
              before 2010-01-02   -->   <@2010-01-02@
              after  2009-12-20   -->   >@2009-12-20@
              on     2009-11-18   -->   =@2009-11-18@
         '%' ->  Match according to a timedelta, for instance:
              in the last 3 days   -->   <%3days%
              before last month    -->   >%1month%
              3 years ago          -->   =%3years%
         '/' ->  Search according to a regex, for instance:
              contains foo                     -->   =/foo/
              contains bar, case-insensitive   -->   =/bar/i
       These available keywords are:
           fp/file : file full path
           le/Time : track duration (in seconds)
           ye/Date : track year
           al/Album : album
           tn/Track : track number
           mt/mtime : file modification time
           ge/Genre : genre
           ar/Artist : artist
           ra/Rating : track rating
           ti/Title : title
           fn/key : file name

       For example, a rule for all tracks by 'Fred' or 'George', which have a
       title containing (case-insensitive) 'the' and 'and', which don't
       include the word 'when' (case-insensitive), and whose modification
       time was in the last 3 days would be written:

         ar=/(Fred|George)/ ti=/(the.*and|and.*the)/i ti=/when/i mt<%3days%

   Notes:
       Paths specified in the MPD config file containing a '~' will have the
       '~'s replaced by the user MPD runs as..

Options:
 -h, --help            show this help message and exit
 -f, --force-update    Force an update of the cache file and any playlists
 -C FILE, --cache-file=FILE
                       Location of the cache file
 -D DIR, --data-dir=DIR
                       Location of the data directory (where we save playlist
                       info)
 -d FILE, --database-file=FILE
                       Location of the MPD database file
 -s FILE, --sticker-file=FILE
                       Location of the MPD sticker file( holding ratings)
 -c FILE, --config-file=FILE
                       Location of the MPD config file
 -p DIR, --playlist-dir=DIR
                       Location of the MPD playlist directory
 -u USER, --user=USER  User MPD runs as
 -n NAME 'RULESET', --new-playlist=NAME 'RULESET'
                       Create a new playlist
 -o, --output-only     Only print the final track list to STDOUT