If someone told you you were as exciting as lettuce, you’d take that as an insult, wouldn’t you? But what if that person meant lettuce the band, not lettuce the boring leafy vegetable? Because THAT Lettuce, a big old funk band from Boston, is pretty exciting. They’ve been making music for over 20 years and it’s pretty obvious that the thrill is not gone. The band called Lettuce play tonight at Brooklyn Bowl.