Active Server Pages (ASP) on Linux
First and foremost: Why not switch to PHP? It performs better, has fewer (albeit certainly some) security problems, is easier to read, etc. See: http://tnl.net/blog/entry/TNL.net_moves_off_Windows
Second, if you won't consider switching and absolutely need ASP:
Sun Java System Active Server Pages (formerly Sun ONE ASP, formerly Chilisoft ASP)
The standard implementation of ASP on Linux is Chilisoft's proprietary
ASP extensions to Apache. Chilisoft has now been bought by Sun
Microsystems:
http://www.sun.com/software/chilisoft/
Sun Java System Active Server Pages 4.0
Sun Java System Active Server Pages software allows organizations to deploy Active Server Pages (ASP)-based web applications on a variety of web servers and operating systems. ASP applications currently supported by Microsoft IIS can now be powered by the Java System Web Server for increased security. Legacy ASP applications running on Windows NT can be transitioned to the Solaris Operating System for ongoing maintenance and support.
An open-source alternative:
ModVB
ASP/VBScript/JScript for Apache
ModVB is a Apache module which aims to provide an ASP/VBScript/JScript compatibility layer for your web-pages. In other words it allows you to run with none or little modifications your ASP pages on your Linux server running Apache.
A bit of perspective
ModVB is based on the work done by Marco Ridoni (mod_gb) and Michael Meeks, Ravi Pratap and other people on Gnome Basic (http://www.gnome.org/projects/gb/), which was meant to be a VB work-alike for Linux. After the successful launch of Mono (http://www.mono-project.com/), Gnome Basic was officially declared "dead". A few months later Marco Ridoni decided to start mod_gb, dropping (even if not completely) the support for GUI elements (Forms, Buttons, etc.) and adding external "class libraries" which could be used to expand the language in real ASP-fashion. The ModVB project was started to improve upon Marco Ridoni's work and create a full featured IIS clone with possible JScript support as well as more objects than supported by standard IIS/ASP.
Current state
ModVB is currently [RM notes: Sept. 2005 — this Web site text unchanged from May 2003] alpha-quality software, maybe even a step behind that. It's nowhere near ready to be installed and run by the faint-hearted, let alone on a production server. If you decide to download, compile and install it, just don't say we never warned you.
JScript has currently not been implemented. We are currently looking at SpiderMonkey (http://www.mozilla.org/js/spidermonkey/) to implement this functionality
Mono Project
What is Mono?
Mono provides the necessary software to develop and run .NET client and server applications on Linux, Solaris, Mac OS X, Windows, and Unix. Sponsored by Novell, the Mono open source project has an active and enthusiastic contributing community and is positioned to become the leading choice for development of Linux applications.
Grasshopper
http://dev.mainsoft.com/Default.aspx?tabid=130
What is Grasshopper?
Grasshopper, the Developer edition of Visual MainWin for J2EE, is a Visual Studio .NET plug-in, which enables you to use C# or Visual Basic .NET to develop, debug and deploy Web applications and Web services that run on Microsoft Windows, Linux, and any Java-enabled platform. Grasshopper supports single-source code development, so you can develop an ASP.NET application that will compile and run on multiple platforms. Grasshopper bundles the Apache Tomcat application server and PostgreSQL database, so you get a complete cross-platform Visual Studio development environment for any platform running Apache Tomcat.