Flycut is a clean and simple clipboard manager for developers. It based on an open-source app called Jumpcut. Flycut is also open source too: http://github.com/TermiT/flycut
Every time you copy code pieces Flycut store them 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.
If you have any suggestions please post them here: http://github.com/TermiT/Flycut/issues
List of contributors: http://github.com/TermiT/Flycut/contributors
Developed by developers for developers.