A Yahoo! Pipe for Twitter
I just published my first Yahoo! Pipe (oh big day, big day!) It adds a feature to the TwitAPI (and here, and here) that I've wanted for a while, which is the ability to get only those Twitter updates that have occurred since a certain time.
You can interactively configure and test the pipe on Yahoo! Pipes.
Note that you must URLEncode the date when testing the pipe via a URL.
One advantage of using Yahoo! Pipes is that my server isn't going to get killed in case this call becomes popular. Another is that it was fun (oooh, pipes!) Of course, the fun only started after I switched to using Yahoo! Pipes on FireFox following a bout of frustration on Safari (Yahoo! Pipes doesn't appear to work correctly in Safari currently and it would be very helpful if the application stated this -- and refused to run -- instead of failing silently when you try to connect a pipe.)
I hope that the Twitterites-In-Charge will add this call to the official API at some point but, until that time, this should cut down the bandwidth used for Twitter mashups, without missing messages.
Update: You can also Get Twitters Between.