Never mind Chrome OS for now; there are already a host of alternative operating systems out there. One such already going for the hosted apps end is Linux-based Jolicloud - it’s just got $4.2 million in first-round venture funding to take it out of private alpha and to target netbook makers.

The Paris startup was brainstormed last year by Netvibes founder Tariq Krim, who, at the time, was trying to build an ethically-produced laptop, but who later decided to focus only on the OS. The funding is led by Atomico Ventures - the VC house of Skype, KaZaA and Joost founders Niklas Zennström and Janus Friis that has previously financed Last.fm, Kyte, Seesmic and others - along with fellow Skype investor Mangrove Capital of Luxembourg.

Jolicloud’s approach is to strip out the conventional desktop GUI in favour of tight integration with web apps (sound familiar, Google?). It’s based on Ubuntu so can run Linux apps, but also Windows software; there’s even a media player app. But, though Ubuntu is still there under the hood, Jolicloud is a web-centric custom GUI that layers over the standard Linux flavour. And Jolicloud says it’s tested on machines made by all the big netbook makers (many of the same ones Google (NSDQ: GOOG) counts as partners).

Zennström, in the release: “Jolicloud is a classic example of a massive disruptive opportunity in a market where high risk has a potential to lead to a high return. Whoever gets it right will be very successful and this is what we love. Tariq’s successful background as a serial entrepreneur makes him well positioned to do this. He’s a great example of a new breed of European entrepreneur who is able to think big and execute well.”

There’s no telling that Jolicloud will be the one to succeed in the race to build the most popular web OS, how disruptive Google will be to the upstarts or whether most people even want to be weened off Windows and Mac OS X. But some big hitters are taking a bet that Jolicloud’s prototyping could pay off. Release (via AC).

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