Kutulu, if you want a more media-center-like experience, you should get a USB IR reciever and run girder, then you can program it to use your universal remote. I do essentially the same thing on my Apple TV...I programmed my remote to think I have XYZ brand DVD player, and then trained my Apple TV to accept the IR codes the remote outputs for that random device.
I also run boxee remote (specifically for boxee) and g-mote (more generally for any application) on my G1, which gives me keyboard and mouse inputs when I need them...but that's essentially cheating
