<off-topic> sorry for ventilating my opinion, but to be honest i don't really understand why a lot of designers always tend to copy 'effects' that are 'hip' ..
i see this kind of stuff everywhere, i would rather create something new of my own..
but that's my taste/opinion </off-topic>
anyway, for creating this kind of stuff (random/generated/algorithmic) you could lokk into any software platform that alows you to actually program the algorithms yourself..
either hard-coding in c++ or java, but you could also look at for instance max/msp/jitter/softVNS, PD/gem/pdp, or scripting languages like director-lingo/-javascript, flash/-actionscript etc..
you could create similair effects dynamically on your website with flash, or even with php on the server-side. there's lot's of ways, but you need to know how to programm...
advantage of pd/gem/pdp and max/msp/jitter/softVNS is that they are visual languages, so you create 'code' by dragging boxes and connecting those with wires.
if you look here for instance:
http://www.bleu255.com/
this design is mainly created with PD/GEM/PDP
This guy only created the software, and set certain parameters, the rest happens automatically, based on parameters the software gets from traceroutes to ip-adresses, and mapping network-topoligies. he also creates music with the same software.
be sure to check the movies on the right side of this page:
http://www.bleu255.com/stm3.php
(nice detail; the microsoft.com domain generated really dark and scary sound and visuals)..
PD/GEM/PDP is opensource / and available for all platforms
the rest is proprietary (except for php ofcourse)
hope this helps
arri