Honestly, I didn't miss leaving behind the DOS command line and getting all GUI. But there are times when I'll still dig out the command prompt window on Windows XP to do something quickly. New service YubNub harkens to give you a command line interface for search. Come up with your own command (it wasn't working when I tried), and then anyone can make use of that on YubNub. For example:
That brings back whois data on Google.com. Use who before any domain you want to check within YubNub to get results. Get the Firefox plug-in, and then any commands you find useful can easily be run from within your search bar.
There are a ton of different commands, some of which work, some of which don't. A full list is here; YubNub Golden Eggs is a list of what's considered the best or most interesting. By the way, if a command isn't recognized, you get Google search results back.
When adding commands works again, I'm going to grab the idea from this example and make a command to search all of Search Engine Watch via Google. It's easy to do the same for your own site. Just use:
Finally, remember that all search engines have command line-like interfaces of their own. Here are links with more info: