Free Ohm Force synth (You do need to register) – Performer Edition, giving you access to all of its mother’s factory presets and some other customizing possibilities.
Regrader provides a delay effect in which the repeats degrade in various ways to provide a malevolent twist on the ears. Download for free here.
RandARP is a free VST plugin arpeggiator with many randomization features, allowing incoming notes or chords to be manipulated in various rhythmic ways.
Sure, VCV Rack is not new and the second post here. But since constantly new versions and modules are being created, here´s a little reminder 😉
Btw, the latest improvent is an unofficial VST patch for fx and instrument use. Installation is a bit of a hassle at the moment though. Support in the KVR forum (Link at the bottom).