As I’ve explained in earlier pieces, I periodically post “most popular” lists of websites (and books) that I think educators might find useful. Of course, there are a number of ways to gauge “popularity.” I just view these lists as opportunities to check-out some new sites, and find it interesting to see which ones might be particularly “popular.”

Today, I’d like to share two tools to use if you want to know which website links are the most popular on Twitter — in other words, what links to sites are being “retweeted” (or forwarded) most often.

There are other similar applications, but these two seem to me to be the best.  I’d be happy to hear if I’m missing something.

One is TweetMeme. It’ll show you lists of the most popular links being retweeted over three periods: “most recent,” 24 hours, and 7 days. You can also view the links by category.

Twitturly is a much more simple application that has fewer categories and only tracks popularly over a 24 hour period of time.

Topsy lets you identify the top 100, top 1000 and the top 5000 links to sites that are being retweeted. Thanks to TechCrunch for the tip.

The other is more expansive than just Twitter but, for lack of a better place to put it, in adding it to the “retweets” list. It’s called Splurb, and it ranks links based on their popularity among several social networks — including Twitter. Thanks to Mashable for the tip.