I like my Kryptonite Evolution Mini U lock; it's probably about as secure as you can get without a considerable amount more weight, and it fits in my back jeans pocket (which is my preference if I'm just running errands). My touring bike has a pitlock skewer and headset cap, and on my cyclocross bike I just run a kryptoflex cable to the front, although this could probably be cut with scissors. I lock with the Sheldon method (U lock the rear wheel through the rear triangle) because I'd honestly be a little surprised if any thief bothered to destroy my rear wheel to steal my bike. If they're prepared to do that they'll probably just defeat the lock itself.

The TiGr lock looks good, if the feedback is still good a few months from now I'll look into it. It's new/different and probably more secure from thieves for that reason alone, beyond any actual properties of the lock.