Flycut is a clean and simple clipboard manager for developers. It based on open source app called Jumpcut. Flycut is also open source: http://github.com/TermiT/flycut

Every time you copy code pieces Flycut store it in history. Later you can paste it using Shift-Command-V even if you have something different in your current clipboard. You can change hotkey and other settings in preferences.

Flycut has been my clipboard manager for several years now and I love its super simple interface with customizable keyboard shortcuts. It can keep up to 99 items in its history, which I’ve found to be plenty.