One thing that frustrated me in the creation of smart playlists on my new podGoober was the apparent inability to use both “ands” and “ors” for logical grouping of music: like “music by the Supremes or Frank Zappa” and “hasn’t been played in a week”.
The iTunes software lets you “and” various criteria or “or” it, but not a mixture.
Hugo Schotman explains the clever hack.