Fun, frivolous, appropriately named Silly’s is a family favorite, a cheap eats jackpot done up in vintage 1950s retro-refined style: Formica tables, tutti-frutti vinyl-covered chairs and stools, fringed lamps, and pressed-tin walls displaying photos of customers with Silly’s bumper stickers in far-flung places. Water arrives in a wine bottle, tea selections in an Elvis lunchbox. The fare is equally eclectic, with vegetarian, vegan, and dairy- and gluten-free options on a menu ranging from burgers and pizza to Thai-style noodles and the Big Fat Greek Dinner ($5.75-$15). A separate menu lists an anything-goes selection of milkshakes, or concoct one from dozens of ingredient possibilities (curry, jalapenos, jelly, peanut butter, bacon … you get the idea). Save room for the ‘‘big as a Buick’’ cookie sandwich.    (Hilary Nangle - Boston Globe)