Background
I want to monitor a running linux system over several days. It's a custom gentoo build and with much custom software on board. This software has ongoing maintenance timers and cron scripts and other clock driven events. I need to verify these scheduled events are working.
Problem
Waiting for the system to step through daily and weekly activity is a long wait time. And modifying all clock-based timers on the system would be time consuming. Yet, I often want to test a system's end-to-end scheduled activities without waiting a week.
Potential Solution
Have the linux system under test appear to run through it's daily cycle of activity within just a few hours.

My Question for Serverfault
Is there a way to cause the system's time to run faster than real world time?

My first thought is manipulating the ntp daemon to repeatedly and smoothly increment the clock . Any other ideas?

And yes, I know this may have strange side affects. However, the system has no important or time critical interactions with systems outside of itself. And this may be a valuable testing technique.