The best happy hour downtown has got to be Coach & Willie's reverse happy hour from 8pm to 10pm M-F.  All of their appetizers, pizzas, draft beer and house wine is half off.  I suggest trying the stuffed Spinach & Garlic Stuffed Mozzarella and a pint of Samuel Adams white ale.  Coach & Willie's is located on 3rd St at the railroad tracks, just south of Jackson St.  For more info:  http://www.coachandwillies.com