I have been using Gmail for a long time. You needed an invitation when it first became my default mail client. Not that that is anything unusual, I mention just so you know I am generally happy with it. It serves my purposes. I look forward to new features and try anything that interests me. I have Labs enabled so I can play with the things there.
However there is one feature I really wanted and it isn’t part of Gmail or even in Labs. That is different signatures for each account. Gmail is great in the way you can use several different accounts in the same screen just like a stand alone email package. I have my regular Gmail account plus my default account from the ISP (just for messages they send) and also an account for a local group I am the secretary of.
Gmail lets you set up a signature but it is used on every email. Not what I want. I have waited hoping this would change but no luck. So I decided to do some searching and found this great Firefox Add-On, as they call them now, “Blank Canvas Gmail Signatures”. Not only does it do what I wanted, different signatures for each account but you can have up to 4 signatures for each account and select the one to use when you create a message if you don’t want to use the default. One for family and one for friends for example.
It is a little unusual in that the options are set within the Gmail Create Message screen and not in the Add-Ons dialog but that makes sense when you think about it. There is a beta version but I am using the last stable version. It is working well for me.