At $945 it's fairly inexpensive, but it only really functions as a webcam.
Have you been Skyping in HD and been horribly disappointed because you couldn't make out every single pore in your friend's face? Well the Flea3 can clear that on up for you – it's the world's smallest 4K camera, and it's designed for use as a webcam.
The miniscule camera utilizes a USB 3 connection for both video output and power, and features a Sony Exmor R sensor for the high resolution video that you're looking for. It's just a little over an inch at its thickest, and it comes in at $945.
Source: Point Grey