Meebo just recently launched its own extension, aptly named as Meebo Firefox Edition. The extension basically adds a Meebo buddy list sidebar (which can be hidden) and a couple of bells and whistles that makes it more useful than a glorified sidebar.
The major convenience that the sidebar provides is the automatic login feature, which is able to log into your IM account automatically when Firefox is started. Once you logged on to Meebo, you'll see your buddy list in the sidebar, which you can select which friend you'd like to message and set your status. The sidebar is resizeable and with the minimum allowable width, the buddylist is still usable without taking up too much screen real estate. The sidebar can be hidden as well, which you can toggle whether it is shown or hidden by clicking on the Meebo icon (see red circle on the first image).
One nifty feature they had included is the alert box feature, which is a small blue box which will pop up on the bottom-right corner of the screen to notify you when your friends were online or when they messaged you. The neat thing is that the alert box is shown even when Firefox is minimized. Not only that, in the Options dialog you can configure what Meebo Firefox Edition should alert you and when it should keep quiet.
At the time of writing it's still in its early stage of development, it still require the actual Meebo page to be loaded in a tab, which is required to contain all the conversation windows and provide other functionality that is not implemented in this extension. So at the moment, what it provides is still pretty basic but it's worth the install just for the desktop alert feature. But I'm definitely looking forward it becoming a full fledged IM extension.
Here's a feature (wish) list that I'd hope to see in future releases:
- Theme-able skins
- Able to configure where the sidebar should be located: either left, right or as a floating window. What I would find it nice is probably something like Google Notebook which is capable to slide out from the bottom
- The login screen should allow a narrower width
- Buddylist groups
- I know this is in the works but I can't resist saying this: Make it standalone without requiring the Meebo page to be loaded ;) (that would mean one less tab :p)
- Audio alerts/notification
- Capability to set MSN display name
To install the extension, head to http://www.meebo.com/firefox and try it for yourself :).
UPDATE: I did forget to mention a quite annoying quirk that if you use the auto sign-in feature, it'll always open a new tab loading Meebo's site. This is quite annoying because I personally use the auto-load previous session feature in Firefox: which make it always end up with two tabs loading Meebo and I have to take the trouble to close one of them. Hopefully that get resolved soon (but then again, the "no tabs" feature is on the way :) ).