Many people who can't quite swing Cambridge rents move to Somerville. Anywhere between Davis Sq and Union Sq is great. I live in the Spring Hill Neighborhood which is right between Davis and Union we have 4 T stops, 3 supermarkets, and countless restaurants, bars and cafes all within 1 mile. This area is dominated by tightly packed 2,3 and 4 family homes which is what has made Somerville one of the densest populated cities in the country. There is currently new lab space being planned/built in Davis and Union Sq.