The demo movie is impressive.
I like how it shows information based on the text typed as I’m typing it. This functionality, called preview, is used extensively in the map command. In fact, most of the time the map command doesn’t even need to be executed, because a small map can be viewed and added to documents without executing a command. I think the preview functionality will be especially useful for looking up programming documentation.
The preview functionality is also used in the built-in twitter command, which posts an update to the microblogging site Twitter. It shows how many characters are left before you hit twitter’s limit. The built-in twitter command, however, uses 160 characters for the limit instead of the 140 character limit on twitter’s website. The 160 character limit for API’s is provided in case a long URL is included in the tweet, which twitter will auto-shorten using tinyurl.
I often post long tweets and don’t want to guess at whether one is going to be too long, so I created my own command, tweet, which uses is.gd for URL shortening. It uses the longest length of is.gd URLs to calculate what the size of URL will be, and bases the number of characters left on that. It replaces any occurrence of the string isgd with an is.gd link to the current page.
Ubiquity might not be the embodiment of a totally new concept, but I find that since it’s a Firefox extension, as opposed to being a desktop application, it’s a lot more convenient for me to use and develop for.