Multiphonics (Playing more than one note at once)
It is not possible to play a complete set of chords on the saxophone, but there are a few fingerings that you can use to play more than one note at once. These are mostly useful as a strange sounding effect rather than to play conventional harmonies or chord tones. As an example here is a multiphonic sound played on alto by fingering a low Bb but without the LH 3rd finger (G):
The same fingering on tenor