$80/night within 20 miles of Boston is a good rate. the benefits of being near the city involve access to the T. driving in and out of the city (especially with the big dig) is like holding your eyelids open with toothpicks until they dry our and start to burn. i live about 3 miles from the city and there is a hotel in my area that is $90/night for a double and it is the cheapest rate around.
while you're here, check out a couple "pubs":
cambridge: john harvard's brew house - a nice brew pub right in harvard square
back bay: vox populi - a 'high-end' restaurant with a young crowd and good music. not cheap,tho.
quincy market: the rack - pool hall and bar. formerly the hang out spot for the red sox, now they all go to whiskey park
north station: boston beer works - another young bar, very fun and not too crowded. try their blueberry beer!
north end: mike's pasteries - go here for dessert. they are open until 11pm, i think and have the best desserts in town
that's my short list. email me for more.