Walking by this store at night and early in the morning is heavenly.
Beyond the smells, the baked goods at Allegro taste great. I like their baguettes, Italian loaf, and sourdoughs. Haven't tried their rye loaves because while I'll eat a sandwich on rye once in a while, I don't love rye enough to buy an entire loaf.
My favorite cupcakes here are the carrot cake ones (and I'm usually a choco-freak). The pumpkin pie bars that Allegro has in the fall are pretty good, though I'm a big fan of cinnamon and other spices and I found the spice factor in the bars lacking.