We have a book with play ideas from babies to toddlers (large, but I can't find it in this mess! :-)) but you can search for "play ideas with baby". Also, walks are great esp. if you interact -- point things out, let him touch stuff, etc. Wait, you're in NYC? Central park zoo, children's museum, ferry rides, brooklyn zoo, transit museum (brooklyn), times square (all the colors!), library (find one with children's read aloud) and check books out. Big fat cars or balls, you could bring him in to the kitchen and let him play with wooden spoons and a bowl (though he's still probably working on coordination). Bubbles, water toys (in bath), Music class for kids. Mainly, at this age, I'd take advantage of the time between naps and get out of the house. You live in a great city (I used to live there) with tons of stuff. Have fun!