needs registration to work? Rated 1 out of 5 stars

Bulk Pagerank Alexa, Yahoo checker

Domain Hammer is the FREE bulk domain checker.

It allows you to mass check:

Alexa Ranking
Google Pagerank
Yahoo Backlinks
IP Address
DMOZ Listing

More than a 100 TLDs are supported. Register to get your free account.

This review is for a previous version of the add-on (1.5.1-signed.1-signed). 

No it doesn't

The addon doesn't need a registration to work.
You only need to register if you want to use the features of the site, which is totally independent from it.