Something like this would do the trick - and there are both cheaper and more expensive variants. You need line of sight of course and these can be triggered by other ...

I never thought Canon got quite enough credit for building full radio triggering functionality into their Speedlight 600 EX-RT flashes, but apparently it has been working for them because now they’re ...

Bringing a new level of versatility and capability to flash photography, the Speedlite 430EX II features a powerful flash with a fast recycling time in a compact, durable body. A one-touch quick-lock ...

The new Canon 430EX flashgun can be powered by the Quantum Battery 1 Compact using the XB2 adapter module and the Battery 1+ with the adapter module MB2.