The Pearl Street Mall (Downtown Boulder Inc., 303/449-3774, www.boulderdowntown.org [1]) started as a 1970s antidote to the indoor mall and has become more than a shopping destination since. It extends along Pearl Street between 10th and 15th Streets, but with shops and restaurants trickling off for several blocks in either direction it now feels like the Pearl Street Mall Area.
In the summer, entertainers hang out on each block—often in front of the courthouse—performing magic tricks, fire-eating, singing songs, making balloon animals, and doing other weird unexpected things to the delight of throngs of people.
In addition to shops like Boulder Bookstore and Peppercorn, there are also carts set up selling hats, sunglasses, and such.
Links:
[1] http://www.boulderdowntown.org