Police say the man behind ballot box fires has metalworking experience and might plan more attacks

50/50 Aluminum powder and rust that's stable enough to resist igniting under a blow torch. What's dangerous about making it?

It's one of the easiest high-energy reactions to prepare, contains only very stable powdered iron and aluminum (though you can add other things as buffers to slow the reaction, such as boron or carbon) and it can only be kicked off by VERY intense heat, like from burning magnesium or the burning titanium powder in a sparkler. Thermite can be shipped through the mail with no special considerations. Were you thinking of something else?

Thought about trying it for kicks, but making the AL powder sounds painful without proper gear.

Making thermite is pretty easy actually!