I keep getting the impression that the event systems designed so far are
only concerned with keyboard or mouse events. These events are then put in
an event queue with some information regarding the event.

Why not define an event as <time, object> and event queue as a collection
sorted by time?
The global event (interrupt) handler detects an event on the queue (tim's
work) and gets the rest of the event of the object mentioned in the event.

In this way, each object (keyboard, mouse, network, etc.) can have it's own
buffer.
And composite events are detected easily by comparing the time stamps.

You could even start new processes to deal with events or have different
event handlers wait on the queues of the objects. No 'centralized' event
queue anymore.

Just an idea.

Reinier.