Would Be A Shame
...it would be a shame if something were to happen to all those blocks you just placed.
This mod increases the power of the next creeper explosion based on how many blocks you've placed since the last explosion. On a server, all players' actions are counted.
Block placement detection works based on the BlockEvent.PlaceEvent, so automated building mechanisms may also be affected by this mod.
Configuration options are also available to customize the explosion power calculation mechanics. Check this great video overview:
UnPacing produced a simple, unassuming FUCKING DEMONSTRATION that really shows off this mod's horrifying potential.