I agree about the Korg awesome! What started me was scoring a cheap OASYS PCI card a few years back. Despite limited polyphony it is a very powerful synth/effects/recording setup. Also it is the only product for which Korg ever licensed their SynthKit program for end users - which is a development environment for prototyping and compiling audio algorithms. They used it for the synthesis engines of Triton, Trinty, Wavedrum, Prophecy, Electribe, and I am sure many others. It includes a module for the target output so the OASYS PCI version only compiles to run on that card. I have run a few of my own crude synth algorithms on it and it was great fun. The SoundLink DRS stuff I often find for quite cheap. A few months ago I bought a 1212 PCI I/O card and 880D/A rack, so the mixer now allows me a convenient way to mix digital audio between two Macs - and the whole pile set me back only a few hundred total. Also the OASYS is great for physical modelling when I want to play with sounds beyond a stereotypical synthy-sounding waveform.

Mac+Mac->ADAT, Mac1212->OASYS FX->ADAT, A4000+Mac->Mac/ADAT... with two Macs and two samplers which are lightpipe fitted, and this mixer and one ADAT - allows for a lot of flexibility for easily trying out new ideas.

As for the Dyaxis II, there is some DSP. I know that the first version used a NuBus card for DSP and interface to the rack. I know even less about the second system. The MacMix program I believe offers basic DSP for summing, fades, EQ, normalization... and coding hooks for including other DSP. Since the platform never caught on like ProTools did there was never any 3rd party development so far as I am aware. Probably not the most useful thing for a modern studio, but quite excellent for what it is. The seller was abroad when I bought it, he just returned and shipped it this week from the next state over. I will follow up in a few days once I get to check it out.

As for tonight I am home from work with hurt knees and will be exploring SoundLink land!