Thanks guys. Once I knew what I was looking for, I realized the problem. There's supposed to be a little plastic thing that goes over the power button (as shown in this picture - http://www.vectronicsappleworld.com/collection/articlepics/pm720075/snap32.jpg). Pretty sure I saw the broken pieces of that in the debris I cleaned out. But knowing that's the power button, I was about to manually operate the button.

It now power's up. Or, at least the power light comes on, the fan spins, as does the hard drive. Should there be POST beeps, or is that just as PC thing?

At the moment, there doesn't seem to be any video signal headed out to the monitor.. and the power button on the keyboard (thanks for the tip about the triangle) doesn't seem to do anything. But I haven't played around with it much... much just be a poor cable or something.

Off to play around some more...

Sal