uudev is a linux program that launches other programs in response to
devices being added and removed from the system. Unlike the
system-level udev program, uudev is designed to be run by users in
their Xorg sessions. Hence it can easily do things like change key
bindings when a keyboard is connected, or kill your screen saver when
your bluetooth phone connects.
The configuration syntax is much simpler than udev. You still match events on properties, but actions consist of arbitrary multi-line shell code. It doesn't provide any device configuration utilities, but does give you access to all the properties set by the various system udev rules.
See the man page for more documentation and examples.