I have a 46" Samsung monitor on my wall (Model UN46C5000) that I use to display the output of some Network Monitoring software we use (Passler, btw.) This monitor is attached to a Mac Mini via the HDMI port.
The one fly in the ointment has always been turning the darn thing on every morning. I know it may seem trivial, but usually the mornings are the busiest time of day of me in IT and sometimes that computer just doesn't get turned on. And I am kind of opposed to just leaving it on and wasting energy.
Now Macs are great at starting themselves up and shutting themselves off, and my Samsung TV has the same capabilities. However it can only turn on and off the the TV input or a USB input, not the HDMI input (which seems pointless to me, but whatever.)
So I turn to my old friend Google. I found a forum on CNET where people were complaining about this exact same issue. A few pages down someone had found a hack that worked around the issue (which the Samsung Rep that was posting to the forum failed to tell anyone which I find both deceitful and troubling.)
Apparantly there is a thing called "Hotel Mode." Like all good hacks, this one has some very dangerous setting that can mess your TV up pretty bad, so use with caution. Also please not that this also has the effect of clearing any of the settings you already had setup (like color settings, timers, time, etc.) Anyway, apparantly on many Samsung TV models, to get into this Hotel Mode, what you do is turn the television off and then press the mute button followed by the numbers 1, 8, and 2 (in that order) and then power on the television again. When the television comes back on there will be a service menu there with all kinds of crazy cool stuff. Digging through the menus you'll want to turn the Hotel Mode to "on" and the Power On Source to "HDMI/DVI”. Once finished, power cycle your television again.
Once that is finished, go in and setup your timers but ignore the source, antenna, and channel settings. They no longer do anything. ;)
And that's about it. I have tested it a few times now and it seems to work great. Good luck and have fun!