For many bloggers, it becomes a bore to have to type in their name, webpage and email address into every form on other blogs when they make comments. This really gets a lot of bloggers cruising around and not dropping their url all over the place. they even do not place comments because of this. This add-on will make that a past issue.
Signature is a Firefox add-on that allows you to insert custom lines of text called signature. There could be multiple. It opens a cache that lets you store as many signatures as you like. You can also name these signatures whatever you like. When you get to a blog and want to comment, it makes life easy. If the blog does not have an autofill and does not recognize you/your computer through cookies, you just go down to the comments box, right-click on the name box and select the stored name which you want to apply to that comment. This comes in really handy for those that operate multiple blog identities.
In the section for email address, you right-click and select whatever email you want to add to that comment. The third one is url and I think that is the most important. Many bloggers and commenters simply put their homepage url. I was doing that for many of my postings on other blogs. However, it makes more search engine sense to add the url to either your latest post, your best post or the post you have which best relates to the article you are reading. That way, any reader at that blog who finds your comments interesting and clicks on your name/url will be taken directly to the related post on your blog. It also may add some valuable external links to your blog. I however understand that links from comments are of less value, almost no real value than links in body of posts. (That is why my contest gives links in posts, get my RSS now and register).
One of the trusted ways of getting your blog out there is through networking. Having a good and ready access to your signature/url makes dropping comments easy and really gets you one inch or two up the ladder of networking. So get this add-on and blast through the blogosphere. You can get there and you will.