Whale Watch Information?

Does anyone know of any place other than the New England Aquarium Whale Watches? I was thinking of organizing a trip out with my research group and associated others, but I wanted to find a couple different places. Most of my searches for a whale watch in the Boston area are just coming up with this one. Also thoughts from people who had used whale watches in the area would be appreciated. I have only gone on the south shore and am not sure if there are more options in the city.