Clipboard History is a very useful clipboard manager. Its main strength over similar applications is that it is very simple, it doesn't take much space on your Menubar and it works well, all the time. The app can either run on the menubar alone, or both the Menubar and the Dock. There is also hotkey support for those users who want to use the mouse as little as possible.
From the moment you launch this application, it will start collecting all the information that you put in your clipboard. In other words, whenever you copy something, Clipboard History will keep a copy for later use. By default, 50 items will be saved, but you can increase this number from the Settings window. You can click the Menubar icon to see your clipboard history. Every item has a number next to it, which is its hotkey. You can easily paste that item by pressing the assigned hotkey. There is also a system-wide hotkey that can be used to call up a window with your history no matter what application you are currently working on.
Something I really like about this app is that it shows the type of the content that is in your history. Thus, if you copy an image, you will see a tag that reads "image", the same goes for text, HTML content, etc. Also, this app worked really well during my time with it. And I like that a sound is played when you copy something to your clipboard.
In short, Clipboard History works like a charm, it is very useful and at only $4.99 is also affordable.