A tool paper about SNAKES has been accepted at the PETRI NETS conference 2015, I'll add it soon to the list of my publications. Additionally, I was pleased to discover that Robert Lorenz was giving an invited talk and that the theory he has presented is implemented using SNAKES.

Here is the abstract from the official program:

Modeling Quantitative Aspects of Concurrent Systems using Weighted Petri Net Transducers, Prof. Dr. Robert Lorenz, Augsburg, Germany.

Abstract:We present a basic framework for weighted Petri net transducers (PNTs) for the weighted translation of partial languages (consisting of partial words) as a natural generalisation of weighted finite state transducers (FSTs). Weights may represent cost, time consumption or probability of a transition execution. PNTs are a general model to consider such quantitative aspects of process calculi represented by arbitrary partial words. Concerning weights, we use the algebraic structure of concurrent semirings which is based on bisemirings and induces a natural order on its elements. Using the operations of this algebra, the weight of general partial words can be defined in a natural way and turns out to be compositional. As desirable, complex PNTs can be composed from simple PNTs through composition operations like union, product, closure, parallel product and language composition. Composed PNTs yield a compositional computation of weights, except for the case of language composition. For the quick construction of PNTs and evaluation of PNT-algorithms we developed the tool PNTool. PNTool is a python library based on the framework SNAKES allowing for the modular construction of PNTs through composition operations, the visualization of PNTs and weighted partial words, and the simulation of constructed PNTs. We present the algorithms implemented in PNTool and use PNTool to show examples for the application of PNTs in the area of semantic dialogue modeling and natural language processing.

Bio:Robert Lorenz is Professor at the Department of Computer Science of Augsburg University, Germany. Prior to this appointment he was Professor at Eichstätt University, Germany. He holds a Diploma in Mathematics and a PhD in Mathematics from Eichstätt University. His research interests concern the theory of concurrent systems. He is member of the steering committee of the „Special Interest Group on Petri Nets and Related System Models“ of the Gesellschaft für Informatik (GI) and editor of its information service "Petri Net Newsletter".

Here you can download PNTool. I've quickly browse through the code and it appears that it has reusable parts, in particular a plugin for SNAKES to handle P/T nets and another to export nets to TikZ.