...or any large furniture store, really. For the REALLY big ones - like most Ikeas - you'll probably want to limit it to one section (e.g. Bedrooms, or Children's area).

Remember to play safe though!

Plus, you get extra points for looking like a loon when random strangers open up the item of furniture you're hiding in, and find you. Pretend you live there, or maybe say that you come with the furniture if they purchase it. Or, just say you're a particularly well evolved woodworm.