Live Chat If anyone is a paid-up member of the open source club, surely it is Miguel de Icaza.

He helped found the GNOME UI and desktop beloved by millions and claimed to be the most popular desktop environment for GNU/Linux and UNIX-type operating systems.

For GNOME, De Icaza earned the MIT Innovators under-35 award in 1999, beating browser daddy and Netscape wunderkid, now moneybags VC, Marc Andreessen.

De Icaza was blessed at the time by GNU and Free Software Foundation (FSF) "saint" Richard Stallman, who reckoned De Icaza was: "Not only a capable software designer, but an idealistic and determined campaigner for computer users' freedom."

But De Icaza didn't stick to the script. In 2001, with Project Mono, he put .NET - which had been developed by a once open-source hostile Microsoft - on Linux and Unix. He also spoke up in defence of Microsoft’s OOXML, incurring the anger of ODF zealots. Now, De Icaza has criticised the cult of Torvalds for damaging the development of GNOME - he reckons the Linux desktop is dead. Meanwhile, his new venture straddles different platforms, while he's hacking code on - shock! - a Mac.

Open-sourcer, hacker, pragmatist... who is this guy?

Join fellow Reg readers for a Live Chat with Miguel de Icaza on 22 March, at 2pm GMT, 10am Eastern, 7am Pacific. Among the topics on parade:

• GNOME past, present and futures
• The web, then and now
• Is the Linux desktop really, finally, really dead?
• Why Microsoft deserved a chance, and how it has changed
• Ubuntu... and the Shuttleworth factor
• Why De Icaza has gone mobile with Xamarin

You can sign up for the Live Chat below and bring us your questions yearning to be free.