try pulling the battery to stop the loop, and then try the following:
Boot into recovery. To boot into recovery, hold x and power at the same time until the "M" appears. Then when the exclimation mark comes up, hit the search button(magnifying glass) on the keyboard. Then wipe data and cache when recovery comes up. Then click reboot. This might take you out of the loop.
If that doesn't work, try plugging into a wall charger, and when or if the battery charging screen comes up, pull the battery, and then try to reboot. You should then go back into clockwork recovery. From there you can restore a Nandroid backup or re-flash a ROM from a zip file.
If that doesn't work, SBFing is the only option I think.