Such a day requires special handling of ones 40k armies - especially with small grade explosives so easily attainable. Big D and I have been discussing this at length and we have developed the following rules for your battles today. Please enjoy the following read, and please let us know if you are foolish enough to blow up any of your models.
For today, and today alone, any model that would fire ordnance must instead place a lit M-60 on the table at the point the scatter die would indicate. This will replace any template needed.
Models that would fire blast templates will replace those templates with a simple black cat (or comparable firecracker).
Lascannons and hunter killer missles will be replaced by bottle rockets fired at the enemy, placed in contact with the firing model, lit and shot at either the opponent or his models.
Of course if a vehicle pops smoke, it must do so with you lighting one of those silly little smoke bombs on top of your tanks.
We would consider this a living rulebook of sorts. If you have great ideas, please dont hesitate to add them!
Happy 4th of July!