I have posted a small update to the Twitter StreamGraphs application to make it more useful. Previously it used Twitter Search to get results for simple queries of the type 'from:twitterid'. Twitter Search currently only gives results going back about 14 days - it used to be much longer. For most people who don't tweet frequently this resulted in a poor quality streamgraph because there weren't many results to work with.
I'm now using the standard Twitter API to retrieve the tweets for any simple user query and it will graph up to a maximum of 1000 tweets irregardless of how far back they go. The difference is shown below for Clay Shirky. The second image shows the new improved results which, for him, go back almost a year. The graph is much richer than the first one which can only base the graph on tweets in the last two weeks.