For a time, Alesis made a line of pedals called ModFX. Two of the better ones were the PHILTRE and BITRMAN (yes, that’s the correct spelling of each).
The PHILTRE was a multimode fiilter offering LPF, HPF, BPF and Notch responses in either 2 pole or 8 pole mode. Fun to place this pedal in the Voyager’s Mix Out jack.
The BITRMAN was a mixed function module, offering compression, distortion, phasing and any one of 6 modulation effects in the same box. The modulation effects (called BITRNESS) include Comb filter, Decimator, Bit Reducer, FM, Ring Mod and Frequency Shift. The order of the compression, distortion, phasing and modulation effects could be changed, so you could phase a frequency-shifted compressed, distorted signal, or bit-reduce a distorted, phased signal that is compressed, for example. Each section had its own control, so if you didn’t want distortion, for example, you could turn it off.
The ModFX line didn’t sell well, so Alesis discontinued the product. Music stores blew them out for $30 each (MSRP was $129). You might find a few places that still have some stock left if interested. Both of these make interesting companions to the Voyager.
Another effect type that creates interesting sonic results is a vocoder. The ModFX line offered one called the MetaVox, but a vocoder function is sometimes included in effects sections of synths (the Roland V-Synth and Alesis Ion come to mind). Synths such as these allow you to process an input like the Voyager, your guitar, etc., through their FX sections, taking advantage of vocoding and any other effect they offer.
Lastly, a company called MetaSonix offers a line of pedals based on tubes that aren’t intended for musical applications. The results from these pedals are said to be wild and wooly - maybe just what you’re looking for.
Greg