Apple’s new iMac goes on sale this Friday. The seventh-gen all-in-one desktop has no optical drive, but sports a ridiculously thin form factor, a new display that saves space using in-plane-switching and LED backlight to produce richer colors, and the latest Intel Core i5 dual-core processors. The big new feature is Fusion Drive, which combines high-capacity hard disks with high-performance flash storage to improve the speed of everyday tasks. There’s also a great new speaker system, a HD 720p FaceTime camera upfront, and the latest ports outback. The 21.5” model starts at $1299 while the 27” mode starts at $1799.