Re: 2004 r6 won't start...
Well first of all, I'll assume you're getting power to everything else (lights, horn, etc.)
The very first thing to do is to check the fuses for the ECU and ignition. There is also a fuse for the ignition coils. There are also a few sensors and switches that could be the culprit, such as the crank sensor. But start with the fuses and come back with an update.
It's obviously extremely unlikely that the ECU is bad, and exponentially unlikely that all four of your spark plugs are bad.
EDIT: Damn you guys are fast lol