If you could kick a ball up a hill & watch it roll back down and use the ball’s position as a modulation source, you’d essentially have the Trigger Accumulating Modulator. Trigger pulses act as the kick, 10 selectable curves give you lots of possible hills, and a host of useful controls help you go a lot further than balls on hills.
Every curve and its inverse are simultaneously output on two jacks, a bias control lets you center the voltage, and a slew dial adds smoothing. Change the magnitude dial for the effect of larger or smaller hills, while also affecting the voltage range of the outgoing control voltage. Climb and fall controls allow you to tinker with the physics, calibrate progress along the modulation curve, and accomplish interesting back & forth movements. Triggers can push modulation along the curve to a maximum, or you can flip the wrap switch so to come back around the other side for some more. A reset jack takes triggers to sync or restart the behavior.
By connecting trigger source from your midi keyboard, progress through this modulation source is now linked to performance and the rate of note changes. By clocking it off of sequencers and such, you have something like an LFO, but whose movement varies with the content. By tinkering with the controls, you can go from smooth progress through a range of interesting curves to jittery back & forth wandering along a general path.
Use the Trigger Accumulating Modulator for a new source of control voltages that’ll make your patches sing.