pbpaste, let you utilise the Mac OS X pasteboard from the command line.
Using it is straightforward:
$ pwd | pbcopy pipes the current working directory into the pasteboard, meaning you can just paste it anywhere by ie. using cmd+v
$ pbpaste also does what you would expect, namely pasting the current contents of the pasteboard to the command line.
...there we go, copy & paste just got nerdyfied :D!