Window Shopping is a little old school and to be honest, fruitless. What do you really get out of it besides tired feet and deep jealously for things you don't have? I personally prefer sidewalk shopping - also a great way for "economical" folk to pass the time and obtain what they need (or don't need). One well kept secret about the fine city we live in is a similar sport called sidewalk shopping.
For the suburban folk, think of it as a yard sale without the price tags. Since I don't have too much time on my hands, as I walk along the streets to my daily destinations, I often find treasures on the sidewalk out on display. They are ripe for the taking as long as you snatch them before the garbage man does.
Now, it's not like I'm digging through my community dumpster, no no no. We are talking quality items that are abandoned on the sidewalk perhaps because someone moved, or upgraded, or no longer has room in their tiny apartment. I see electronics, books, baskets, couches, dishes, vases, brooms... One time I saved a microwave from it's destined doom and gave it to our friends who didn't own one.
Anyway, several times a week as I'm strolling down the street I can see a piece of furniture in the distance that I covet as a pass. I will deeply regret that round coffee table I didn't haul up to my apartment because I didn't know where I would put it. Next time I will impulse shop and live by the motto take first and figure out where it will fit later. If I lived in a two bedroom I would furnish the guest room with sidewalk shopping trips.