Gaggle is used to derive regulatory networks, but it's not a
"push-button" process yet. Our lab published a predictive regulatory
network for the model organism Halobacterium salinarum in this paper:
A predictive model for transcriptional control of physiology in a free
living cell.
Cell. 2007 Dec 28; 131 (7): 1354-65.
Bonneau, et al.
We used software called cMonkey and Inferelator (both R programs),
described here: http://baliga.systemsbiology.net/
Applying similar methods to eukaryotes is a work in progress.
-chris