This is a really cool project that was on kick-starter.http://www.kickstarter.com/projects/597507018/pebble-e-paper-watch-for-iphone-and-android
You link your watch up to your iPhone or Android Phone using Bluetooth and you are able to get notifications and data that is sent between the two devices. You can get cycling information using the GPS in your iPhone and have the results beamed to your pebble watch. You can see your emails, texts and caller ID on your watch, all without taking your smartphone out of your pocket. The Pebble SDK allows you to create your own apps that work with the pebble and you install them directly of your iPhone using bluetooth to get them onto your pebble watch.
The watch uses an eInk screen, so you can see the watch outside easily even in direct sunlight. It is on kick-starter now and is just $115 + $15 postage else wise it will be in American retial stores for just $160US around September time. Oh and did I mention that the watch is also waterproof, has an inbuilt accelerometer, timer, 7 day battery life, EDR and an ARM processing chip that is similar to that of the iPod touch 2nd generation?
Furthermore, the watch has received huge consumer response raising $3 million in just a few days on the kick-starter website with thousands of backers. Just check out the video on the main page if you are unsure of what the watch actually does and have a look at some of the app pictures as well.