While I have a smart strip in my cabinet now, I find it is very finiky on detecting the PC power. Depending on where I set the sensitivity, it either doesn't turn the monitor on, or doesn't turn it off. I've gotten to a point now where it will *eventually* turn it off (think hours), but its still frustrating.
Instead, I've decided to try a new computer PSU that an extra AC Outlet in in (Vantec 420 for the interested). The outlet in only energized when the PC is on, so it should do the trick (in my case, its only the monitor that I'm trying to sync power with the PC)...
I'll report back when I get it and get it installed.