AudioGuru.
It has 4 modes (5 really) of operation.
Home
Work
Sleep.
Normal
(Auto - Time Based)
You can schedule the 4 different modes to come on at various times in 15 minute intervals. in each mode you can set the volume levels for Voice, Media, Ringer, Alerts, System, Alarm. and control the vibe for Ringer and Alerts.
Very nice app. Free as well! Free is limited to one schedule for all days of the week. Pro version allows you to differentiate between weekdays and weekends. I just need it to silence the Fing battery charged alert!
It has a few nice widgets if you like quick access to the various modes and such as well.
the only thing that would make it perfect is a timer based Silent. Since there are times I'd like to silence the phone and not have to remember to turn the sounds back on it would be nice to say run Silent for 1 Hour.