Last week I offered anyone who might be interested a copy of the batch files and other tools (cURL, grep, my nasty little program and the Excel spreadsheet) for analyzing Twitter "Tweets" – all you had to do was send an e-mail to gearhead@gibbs.com with the subject "TA". I've had quite a few requests and you will get the files in a few days – the delay is because I found a bug in my nasty little program and I haven't had time to fix it.

While the Excel approach to analyzing Tweets was interesting, I admitted all along it was clumsy and ugly. So if you want to keep track of a current hot topic, say, a mildly interesting topic such as swine flu, how else might you do it?

You could search for exactly that term you're looking for, but with Twitter Tweets there's another way to look for relevant content using "hashtags."

Hashtags is a convention that uses a hash mark (#) to flag words in Tweets that users want to be treated as description tags. Thus, the hashtag for swine flu could be "#swineflu" (spaces aren't allowed so hashtags usually merge the words or separate them with dashes or underscores).

While we're on the topic of tags you might want to check out "Tagging: People-Powered Metadata for the Social Web" by Gene Smith (also see Smith's Web site for more on tagging). This book contains useful information but is somewhat dry and more suited for a technical audience (it also has a fair amount of code). Curiously, it mentions nothing about Twitter or hashtags despite being copyrighted in 2008. I'll give it 3 out of 5.

Anyway, hashtags can be searched for on the aptly named hashtags.org, which is way smarter in this area than Twitter's own search service because hashtags.org will also give you a list of all of the other hashtags that contain the same string. Thus, along with #swineflu you'll see the tags #swineflu, #swineflue, #swineflu-cbc, #swineflu-related, #swineflu-ing, #swineflu-nz. This can be really useful as the great unwashed occasionally pick an incorrect spelling (#swineflu-cbc, for example, was apparently an attempt to type "#swineflu-cdc").

What's great about hashtags.org is that clicking on a specific hashtag amongst those suggested will take you to a page that shows a graph of the hashtag's popularity over the past month (which wouldn't work for the term "rovio" that we've been discussing over the last few weeks as it appears no one has used it in a hashtag).