Everyone keeps suggesting placeable clocks, and it's a good idea, but we can do better. How about making the placed clocks actually useful?
Clocks should provide redstone power only at daytime and not at night. This could be used for street lamps, for example.
In addition, they should be settable by right-clicking to change the timer. For example, the default is "redstone at day, none at night". You could set it to alternate every Minecraft hour (or every 2, 3, 4, 6, or 12 hours). This could be used for bell towers and time bombs, for example.
This would provide a fitting functionality for a normally useless item. A lot of people want to be able to schedule redstone, and you can only do this with some complicated grass or villager mechanism.
Clocks should provide redstone power only at daytime and not at night. This could be used for street lamps, for example.
In addition, they should be settable by right-clicking to change the timer. For example, the default is "redstone at day, none at night". You could set it to alternate every Minecraft hour (or every 2, 3, 4, 6, or 12 hours). This could be used for bell towers and time bombs, for example.
This would provide a fitting functionality for a normally useless item. A lot of people want to be able to schedule redstone, and you can only do this with some complicated grass or villager mechanism.
Sorry, the search is bad.