wildcard bookmark

I don't know how well-know it is, but basically you make a bookmark with a keyword for the address bar and a wildcard in the URL.

For example, if you make a bookmark with the keyword 'map' and the address 'http://maps.google.co.uk/maps?hl=en&q=%s' (note the '%s' wildcard) you can then type 'map cleveland street london' straight into the address bar just as the summary suggests. All that they seem to be suggesting is having it come up in a 'floating' context box like the AwesomeBar rather than actually open in the tab.