Here is a DIY kit that lets you build your own spy camera. The Zetronix Nano Pro is a tiny pinhole camera that coverts any object into a nanny camera with a wide 78-degree lens. It can record audio too. It sends motion alerts to your phone. You can record 100 minutes per 1GB.
This spy camera comes with 1 year battery life on standby. It has infrared LEDs to capture video in dark rooms. You can find out more about it here.