So I was freaking out over the pagerank my Google toolbar was giving me for one of my sites and I ran across this neat little tool.  It's more than a simple pagerank checker.  It will check your pagerank, tell you the age of the domain, the Alexa rank, if your site is listed in the Yahoo or DMOZ directories, give you backlinks and indexed pages, and most amusing of all, calculate the value of your website.  It will also allow you to enter an email address and it will send you updates for your search.

Smart PageRank