Spectral Suite is a selection of free FFT based plugins.
Spectral Gate let through frequency components above a certain cut-off point or reverse this to only let through frequencies below the cut-off.
Sinusoidal Shaped Filter impose the positive part of a cosine shape onto the spectrum. Changing the phase, width and frequency will morph between classic filter shapes.
Frequency Magnet focuses the spectrum upon one single component. Morph between this and the clean signal to gradually reduce the spectral width.
Frequency Shifter shift the frequencies up and down along with a vibrato to modulate the shift.
Bin Scrambler randomly map the content of one frequency component to another at a set rate. Interpolation for each scramble allows smooth shifting between sounds.
Visit: Spectral Suite