If this was already posted before i'm sorry, after spending some time with google i couldnt find anything about this and i'm actually surprised nobody noticed this yet. Forget about those task killing apps. Regular programs and widgets like mediascape, timescape and other small widgets are not the problem with the X10. Those all idle happily without sucking any CPU cycles. The problem is the face recognition service running in the background. You can kill this via Astro and it wont come back until you reboot. This service tries to recognize faces from everything thats displayed on the screen, what a stupid idea. Anyway by doing that it eats 20-90% CPU power while using the cellphone (see photo, Astro idle). I guess this service only truly IDLEs when the screen turns off, so it probably wont save much battery when not using the phone, but the UI is ALOT more responsive without that service running. I especially noticed the difference with ACV (comic reader) where you had to wait 4-5 seconds for every picture to load, while now without, pics almost load instantly. Another small but nice "tweak" is simply removing the protective film that comes from the factory on the X10 (the 2nd one). After that the touchscreen get's a bit more responsive. By the way I never thought the X10 was laggy to begin with, but now it's a real joy to use!