Has anyone hacked the dashboard to display upcoming milestones that are within x number of days? I noticed today that aC displays upcoming milestones due tomorrow...where is that code and can it be configured to show a longer timeframe?

Thats a good question.. I took a moment and followed the following function: $project->getUpcomingMilestones())

So check these 3 files.. I'm sure you'll find what you need.

application/models/Projects/Project.class.php.
application/models/project_milestones/base/BaseProjectMilestones.class.php
application/models/project_milestones/ProjectMilestones.class.php

Also found this thread:
http://www.activecollab.com/forums/topic/1443/