Mac users have long enjoyed a cool application launcher called Quicksilver. Personally, I have a love-hate relationship with Quicksilver since Spotlight's application launching feature is pretty much enough for my use.
Anyway, Linux is now blessed with a similar application launcher. Whilst it may not (yet) be as as feature-rich as Quicksilver, I am betting that its open source nature will allow it to quickly surpass Quicksilver in form and function. Called the Gnome Launch Box, this GNOME application was inspired by Quicksilver – notice how Quicksilver looks like in the image? Check out Gnome Launch Box and you will see similarities. :)
I am optimistic that Gnome Launch Box will improve by leaps and bounds in the near future but only if there are developers who know how cool Quicksilver on the Mac really is.
um… katapult for kde has been around for a while. http://katapult.kde.org/