Commons-IO contains utility classes, stream implementations, file filters, and endian classes.

Apache Commons JEXL is a library that enables scripting features in Java applications and frameworks..

Alternate implementations of JDK's "Math" functions.

Apache Commons Email provides an API for sending email, simplifying the JavaMail API.

Apache Commons VFS is a Virtual File System library.

Apache Commons Exec is a library that reliably executes external processes from within the JVM.

The Math project is a library of lightweight, self-contained mathematics and statistics components addressing the most common practical problems not immediately available in the Java programming language or commons-lang.

XML Graphics Common Support

The Commons Jexl library is an implementation of the JSTL Expression Language with extensions.

General purpose classes for use with the JCR API