I have seen quite a few code bases, where the original author who didn't want to continue the project, just released the source code somewhere (as zlib, public domain, GPL or what ever) but nothing more.

If there was interest by some other developers, there was always some new open source project/community building itself up around the released code. And if not immediately, maybe a few years later.

E.g., some examples (where I was partly also involved in):

* OpenLieroX http://openlierox.net

* ioquake http://ioquake3.org/

* many projects here: http://icculus.org/projects/

* iodoom3: http://www.iodoom.org/ http://git.iodoom.org/ (still not much content there)

* https://github.com/id-Software

* Commander Genius: http://clonekeenplus.sourceforge.net/

* https://github.com/LaPingvino/The-Puzzle-Pits

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