The PL/SQL Utility Library, codenamed "Alexandria", now has a new home at GitHub. This will make it easier to collaborate on the project. If you want to contribute, just fork and submit a pull request.
The liibrary contains around 50 PL/SQL packages as well as a few types. There are no table dependencies, which reflects the general-purpose nature of the utilities. Jeffrey Kemp has a great guided tour of the library which highlights some of the packages.
Before the move to GitHub, the latest version (1.7.0) had been downloaded almost 7,000 times, and all versions a total of 12,000 times. So I guess it's being pretty widely used...
You can download, clone or fork the library at https://github.com/mortenbra/alexandria-plsql-utils