Hello Lars!
Ola info can be found here...
http://www.opendmx.net/index.php/OLASome Mac DMX software uses it to implement Artnet connectivity (among many other protocols like Shownet)
I think it makes available 6 possible artnet universes.... Works dandy with my Enttec ODE but was quite confusing for me to setup, but bulletproof once working. Am a semi-techy artist type, but network configs baffle me. Mac/Linux
The software I am using with OLA is called QLC. a neat little package that allows "roll your own" control interfaces...
I use it for small dance shows with lotsa LED pars and such, but will control movers great. Linux/Mac/PC very stable on Mac.
qlc.sourceforge.net
cheers!
jd