Note for Overclockers
Overclocking does not seem to make noticeable difference in UAE4All yet it will generally consume 100% CPU between it, Xorg and PulseAudio. As such its better for the health of your N900 (and battery life) to use 600Mhz max while using UAE4All as you will just be heating up the N900 and draining the battery for nothing.

http://wiki.github.com/smokku/uae4all/compatibility

not sure who wrote this, but i wouldn't agree at all, demos are stuttery on the sound at the standard clock rates. work perfectly when overclocked!