I grew up using the command line. And then with the Mac, Windows and the Internet - it was gone.
But it's been coming back slowly.
I've been thinking about the "web command line" for a while.
Yes, Google Search is a web command line for years now, doing conversions and calculations (to name a few) and not just search.
And there's been some attempts to take this further, like yubnub.org
But recently the command line is creeping back in web's true style - unnoticed, uncoordinated, distributed. Slowly and surely.
It's in twitter where you use prefix characters to denote other users and topics in a text box inside your browser.
It's in blip.fm where you control broadcasting to other sites by a prefix exclamation mark in a text box inside your browser.
It's in aardvark where you interact with other users using text commands in the text box of your IM client.