Some of us just don't have the space for a projector to be permanently set up - that is why all these models are quick to set up and have integrated speakers; while HDMI connectivity means there is only one cable to connect for both sound and video.
If you really want to create that big-screen experience, models with a special "short-throw" lens* can give you a 120" image from less than 2m away - ideal for shadow-free gameplay on your Xbox, Wii or PlayStation 3, even in the smallest of rooms... now in awesome stereoscopic 3D!