OpenBSD vs. NetBSD
NetBSD was trucking along in 1994, well on its way to being the “runs-on-anything” Unix. Theo de Raadt was one of its developers, working on the project. Unfortunately, his abrasive style rubbed people the wrong way, and in an e-mail to the NetBSD users list, the situation was laid bare:

On December 20, Theo de Raadt was asked to resign from the NetBSD Project by the remaining members of “core”. This was a very difficult decision to make, and resulted from Theo’s long history of rudeness towards and abuse of users and developers of NetBSD. We believe that there is no place for that type of behaviour from representatives of the NetBSD Project, and that, overall, it has been damaging to the project.

Theo took his toys and went home, where he started OpenBSD, a Unix project that is still rolling to this day.
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OpenSSH vs. SSH
Not dissimilar to the OpenBSD kerfuffle is the OpenSSH project, which was created by the OpenBSD team. When version 2.0 of SSH switched from a free license to a commercial one, the free software community was incensed. As a result, the OpenBSD team forked the last 1.x version of SSH and created OpenSSH.

This move caused some consternation for Tatu Ylonen, the creator of SSH and the man behind its commercialization. He voiced his distaste in an e-mail to the OpenSSH users list:

I have started receiving a significant amount of e-mail where people are confusing OpenSSH as either my product or my company’s product, or are confusing or misrepresenting the meaning of the SSH and Secure Shell trademarks. I have also been informed of several recent press articles and outright advertisements that are further confusing the origin and meaning of the trademark.

The battle over this essential tool eventually cooled, and today, OpenSSH remains in widespread use within open-source Linux and Unix distributions, while SSH remains a successful security company.
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LibreOffice vs. OpenOffice.org
From the moribund OpenOffice.org has come an actual, moving project, dedicated to advancing the ever-behind open-source office suite.

The bright and fresh LibreOffice project is actually drawn away from drama, and it tries only to speak of the positives rather than dwell on the neglect shown to it by Oracle, and before that, Sun. In the first few months after the LibreOffice fork, many lingering bugs had been fixed, and entire chunks of unused code had been removed from the rotting codebase. With the new spirit in this project, LibreOffice might just finally fulfill the promise of OpenOffice.org: to provide an alternative to Microsoft’s Office suite.
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Xorg vs. XFree86
Remember the days of XFree86? The X Windows server used by most Linuxes before 2004 was originally built for the old IBM compatible PCs, but as Linux grew in the 1990s, it became the de facto basis for most Linux windowing interfaces.

But in 2003, the project was rife with drama and upheaval, much of it focused on Keith Packard. He saw the project as failing because of a lack of community involvement, mostly thanks to the structure of the decision-making process for the project. In Packard’s own words:

The key issue is that XFree86 is not a community-governed project. XFree86 processes and procedures originate with the Directors of the XFree86 Corporation. Technical leadership of the XFree86 project has traditionally been provided by the XFree86 Core Team, an informal association of leading XFree86 developers.

Packard and others forked and started their own work. Today, Xorg is the standard for most Linuxes, and the Xorg Foundation seems to be handling the project with limited internal kerfuffle potential.
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Hudson vs. Jenkins
Finally, just when continuous integration in Java was getting to be downright enjoyable, the inevitable drama llama reared its head. Oracle claimed ownership of the name Hudson, via its Sun acquisition. The community took its code, renamed it, and carried on as Jenkins.

But the fighting continued for another month, as both sides tried to discuss the matters that sparked the fight via blogs ad Twitter, and even at SD Times’ site.

But in the end, the actual event that sparked this whole kerfuffle turned out to be a non-issue. The proposed move of Hudson to GitHub, which first caused Oracle to balk, happened anyway. Now, both Hudson and Jenkins are hosted on GitHub. Go figure.