18MP APS-C CMOS sensor, 9-point AF system, ISO 100 to 12,800, 3-inch touchscreen, built in flash, hotshoe, SD card slot, 1080p video, 4fps continuous shooting, 407 grams
Unbelievably tiny for a digital SLR, optical viewfinder, touchscreen, various effects
Small battery, does not provide a secure grip for people with large hands
One of the major reasons that people don't want to buy DSLRs is the added bulk/weight. If you're one of them, the EOS 100D might convince you — it's the world's smallest and lightest full function (with mirror) digital SLR with an APS-C size sensor. With the included 18-55mm kit lens, the camera weighs just over 400 grams and is about the size of a small prosumer or Micro Four Thirds camera.
Canon has managed to shrink all the components down without really omitting anything. In fact, it has an optical (through the lens) viewfinder, a 3-inch touchscreen and a full array of properly-sized buttons (so that you don't have to use the touchscreen if you don't want to). For all intents and purposes, this small DSLR can do anything that a larger one can do — you have support for external flashguns, remotes & microphones, HDMI out for connecting to TVs, built in creative filters (fish eye, toy camera, miniature etc), speaker, RAW support and custom modes.
You can also use the touchscreen for things like tap-to-focus and tap-to-shoot. Image quality is at par with any mid-range DSLR and you get excellent results all the way up to ISO 1600. Possibly the only real compromise made here is the battery — the smaller Li-ion battery is good for about 200 to 300 photos. Another point to note is that it may be too small for people with medium to large sized hands — if you have large hands, you may find that you can only grip the camera with three fingers instead of five. You should buy this camera if you want the smallest 'proper' DSLR around.
If you need something even smaller, you can get excellent results from Sony's NEX-6L. The NEX also has an APS-C size CMOS sensor and comes bundled with a 16-50mm lens.