Jeff Atwood had it right, why isn't clipboard history baked into the OS?
In my day job I develop websites on Windows 7 and in my spare time I develop iOS apps (and my own web app Vote Daily Deals) on OSX. My day is spent copying and pasting all day long. Wether it be a variable for SASS or a Gist snippet. Given that if I could only copy and then paste one item at a time, that wouldn't be very productive. Unfortunately clipboard history with a context sensitive UI isn't a standard feature in both Windows or OSX in the year 2012.
To get round this shortcoming of both platforms I have to use small applications to do this. For Windows I use Ditto a free Open source application that saves a clipboard history (and is also searchable). For OSX on the Mac I use a great freeware app called ClipMenu. Both work in a similar way. Use a global shortcut combination and you then get a menu right where your mouse cursor is to select the item you want to paste into your current application/text editor/IDE.
Not exactly earth shattering stuff. Used throughout your day when you can blissfully copy text without having to right then and then go use what was copied at that point in time... Well you get the picture. This is such a fundamentally huge step forward, why isn't just part of the OS? Do yourself a favour install one of these apps today.