The following quotes are all unsolicited.

I think aiSee is a very useful tool in compiler engineering. 
Gerolf F. Hoflehner, Intel

I used aiSee with basic needs for language grammar visualization (morphology). The program did the job beautifully. 
Jean-Marc Coursimault, Xerox

aiSee is a very useful relationship viewing tool that allows the user to explicitly define complex graphs. 
Chad E. Storer, Pharmacia

I would like to thank you for creating such a great node graphing software. I have been working on creating maps of the gnutella P2P network, and aiSee has outperformed every other node graphing software I have tried. 
Gregory Bray, GnuMap

I like aiSee; it has many more features than the software I was using before (dot), especially when working with large graphs. 
Dennis Wollersheim, La Trobe University

For my master thesis, I have reviewed five graph layout tools with regard to their tree visualisation capabilities. aiSee proved to be by far the most suitable one. 
Norbert Pfaffinger, Vienna University of Technology

We chose the aiSee software for our graph layout, because it was very easy to learn and yet provided all the flexibility to produce very informative, data-rich graphs. The generated pictures provide a powerful tool to explore the large multidimensional datasets produced by modern post-genomic technologies, such as gene expression arrays or metabolomics. Our biologist customers just love it. 
Rainer Breitling, University of Glasgow

aiSee has been very useful to me, it was just the kind of tool I was looking for when I found it! The thing I like most in aiSee is that it is very simple to start drawing graphs. You can write just a few lines of code and see how a graph is born. That's nice! 
Ricardo Sanchez Alonso, Universidad Carlos III de Madrid

We selected aiSee for its ease of use, simple installation, availability (runs under various OS), functionality and performance in rendering. 
Nyik San Ting and Ralph Deters, University of Saskatchewan

Developing complex software systems such as highly optimizing compilers is not to be taken lightly. As the complexity of projects grows, it becomes more and more difficult to maintain a proper perspective on all relations and interactions. This is when a good visualization tool can come in handy, providing a better understanding of how complex systems really behave by means of graphs in many flavors. <...> aiSee can be very instrumental in evaluating the effectiveness of a particular (own-developed) analysis, or optimization engine. 
ACE Associated Compiler Experts

I am really impressed with your service. On two previous occasions you have promptly replied to my queries and even sent an example GDL file when I asked for it. Keep up the good work. 
S.Ravichandran, Dubai

I have been using aiSee for several months and I am very happy with it. It has proven to be an easy way of displaying and manipulating graphs.
I am involved in finding genes underlying genetic diseases in dogs, which may serve as models for human genetic diseases. In this context, aiSee has helped me a lot. It allows me to obtain the best layout for the complex pedigrees typical of highly inbred domestic animals. It also makes it possible to manipulate interactively the graph. 
Jesús Aguirre-Hernández, University of Cambridge

I downloaded aiSee, because I heard that it is one of the most powerful graph drawing tools in the world, and it is great. Great! 
Jay Duke, Etri