This is a great archive of pyro formulae. Sadly, the author took it down as a result of the actions of a moron (familiar story, unfortunately). On his site he has given permission to others to put it on their sites, which is what I have done as I believe it's a great collection. The original site address is www.come.to/pfp If he changes his mind, this is probably where the up to date version will reside in the future. I downloaded this version a couple of years ago, I don't know if a more up to date version exists.
The author is Andrew Krywonizka, who must be given all credit for this work.
Black Powders
Burst Comps
Flash Powders
Fountains etc
Other Comps
Rockets
Smoke Comps
Stars
Tracers
Whistle Mixes