Sinevibes have just released Atom a filter with focus on dynamic, tempo-synchronised modulation.
Best of all it's absolutely free
Here are the specs:
– Multi-mode filter with five types and –12/24/48 dB/octave slope steepness.
– Dual modulators with eight waveforms, per-cycle chaos function and shape lag on/off switch.
– Advanced transport sync algorithm with support for tempo and time signature automation.
– Extensive use of OS X Core Animation and Accelerate frameworks for hardware-accelerated graphics and audio processing.
http://www.sinevib.es/atom/