Linux on Sun Niagra

Linux can now run on Sun UltraSparc :: Linux's been running on IBM's Power processors for a few years now.
UltraSparc is now an open source chip :: Power.org has also been around for quite some time now (chip design available here, among other things)

People are skeptical about Linux on Sun.

The ZDNet article covers IBM's, HP's experiences with Power and Itanium respectively.

"Faced with difficulties getting Intel's Sparc rival, Itanium, to catch on, HP is underwriting a large portion of a five-year, $10 billion effort to popularize the chip family."

The largest distributors for Linux, Red Hat and Novell, don't support Sun.

"Red Hat dropped its Sparc support in 2000, and Novell Suse's last supported version was released in 2002."

"The effort is part of Sun's attempt to restore its relevance and financial fortunes by shaking its image as a proprietary technology company. That legacy from the '90s hurt the Santa Clara, Calif.-based company when it missed out on two major growth trends that spanned the rest of the server industry: machines built with x86 processors such as Opteron and Intel's Xeon, and the open-source Linux operating system."