The Qt XInput Extension is a C library adding support for XInput devices (like tablets or joysticks) to Qt-based X11 applications. QXi supports devices with up to six valuator axes in absolute mode, up to 32 buttons, and any number of keys. It is built using autoconf and libtool, and comes with a simple example application.
Ivman is a flexible userspace volume manager for Linux. Originally an automounter, it can also be used to run arbitrary commands when certain devices are added to or removed from the system, when properties on existing devices change, or when devices emit conditions. Unlike gnome-volume-manager, it runs from a console. It uses D-BUS and HAL to listen for new devices, and uses pmount for mounting.