"Biker Jim's Gourmet Dogs": That's the sign hanging from the cart, complete with a laughing, bandanna-wrapped skull that gives the name a little outlaw flavor. The cart is a beauty, too: lots of stainless steel and polished aluminum, twin umbrellas and a full grill. Biker Jim (aka Jim Pittenger) works with his radio playing, surrounded by coolers full of soda and cute, fluffy animals all turned into sausage links. He works in the sun and in the cold. He shows up early and stays late. He gives away free samples to passersby who stop, stunned, when they catch a glimpse of his menu of woodland critters. As far as we know, Pittenger is Denver's only purveyor of authentic Alaskan reindeer sausage. And German white-veal brats. And wild-pheasant sausage. And boar. And while several real restaurants in town sling the occasional buffalo sausage, we're certain that no one else is serving that sausage studded with jalapenos and slicked down with Sriracha sauce, as Jim does at his cart.