Today and tomorrow you can run the Insane Inflatable 5k for a steep discount. Through Friday registration is only $64. Signing up at the gate is $75 (still worth it for the funnest run of 2015). And as of Thursday morning, only the 8:45 a.m., 9 a.m., 11:30 a.m. and 12 p.m. waves are open. If your friends are running in a different wave, you can still sign up for ANY wave for $100.