For those of you who are new to these things, NASL stands for Nessus Attack Scripting Language. NASL is part of the closed-source Nessus vulnerability scanner and its open-source form called OpenVAS (Open Vulnerability Assessment System).
Nessus plays big part in the hearts of many administrators, security consultants and scanning vendors. Nessus practically was the first stable and well maintained open-source security scanner until they closed the source.
So, what about NASL? My point is that we don’t need it. Recently I had to work with OpenVas and Nessus in order to automate some trivial penetration testing practices. I’ve worked with both and I got fed up with NASL. I still cannot understand why on earth we need yet another general purpose scripting language which looks like some kind of a hybrid between PHP, C and JavaScript.
Anyway, so since version 3 Nessus is closed source. Now we have OpenVAS, a 2.x fork of Nessus. The project is coming nice but still far from begin good enough for environments where stability is a must. At some point I decided to contribute since I am particularly interested in haviong a free Nessus clone with a good community behind it. As soon as I started putting down some code I realized that this is not what I want. Nessus’ code seems undeservingly complicated.
In reality I do not need Nessus neither NASL. All I need are the tests. I believe that everybody feels the same. Perhaps the whole OpenVAS project should concentrate on writing the tests and let the user choose the engine. In my case Nessus was not a good engine due to license limitations. OpenVAS was not a good fit as well because of stability reasons. I am stuck!
It occurred to me that because NASL is very close in syntax to PHP, JavaScript and C, it will be actually easy to rewrite the scripts in a more suitable language that has a better community around it. Of course everything needs to be done in an automatic fashion because I hardly doubt that anyone have the personal time to sit and rewrite boring NASL scripts, unless he is paid good money for. This is not how things work in the open-source world though.
Unfortunately, I do not have the time to start such a project although I will most certainly contribute. I hope that someone is willing to take on the challenge. Any takers?

I find myself leaning towards nmap, w3af, and metasploit for all my developments.
Nmap has a great scanning engine, and with the the lua interpreter and nmap libraries it makes a devent development environment for general discovery scripts. It has replaced Nessus for me in my development.
W3af is growing into a decent web testing tool, though it definitely has its own problems and quirks and consumes too much memory. It’s written in python, and can be easily extended. Paros is more stable, uses less memory and works better for many tasks at the moment, but the architecture is an evolutionary dead end.
Metasploit is written in ruby and has the best general network packet manipulation libraries I’ve ever worked with, and is great for all manner of packet creation and discovery tasks.
Given the new BSD license, when I build any new security tools I will strongly consider either writing them for metasploit, or borrowing some of their libraries. They have done an excellent job of taking the best in class ruby libraries and extending them to be even more useful.