Apple should produce a nice ergonomic keyboard. Since they don’t, I’ve resorted to using a Microsoft wireless natural keyboard and mouse. Microsoft has Mac drivers that add a new control panel to the system preferences, and other than my needing to remember that the Alt key is really my Command key everything is good. Except for the first couple times the Mac went to sleep. With the original Apple keyboard I would press a key or move the mouse to wake from sleep, but this won’t work with the Microsoft keyboard. I needed a workaround.
The first tip is that you can wake a sleeping IR enabled Mac with your Apple Remote Control. If your Mac is sleeping and unresponsive to keyboard and mouse input, this is the thing to try before you resort to power cycling it.
The second tip is to configure your Mac so it gets as close to sleep mode as possible without really sleeping. I have mine set to shut down the monitor after an hour and to idle the hard drives whenever possible, but to never sleep. This is configured in the System Preferences->Energy Saver panel. Since hard drive life is my real concern with the Mac always being on, this configuration lets me get the most important benefits of sleep mode while still responding to the keyboard.