Kool IM
Kool IM comes right after Meebo in terms of functionality, but it’s the most unpopular of the lot, and there’s a few reasons why. Like Meebo, it let’s you login to all the popular messenger services – MSN/Windows Live Messenger, Yahoo! Messenger, AOL Instant Messenger, ICQ, Google Talk—at the same time. It does, however, pop out the actual contact list window, and each conversation gets its own window, but this may be convenient to those who are used to conventional instant messengers that each take up a task bar item, but not to those who prefer to tuck away all their conversations in one window for easy dismissal. It looks quite nice, but beyond that, it’s a very basic messenger. It doesn’t support smileys!

Messages Sur Le Net 2 Go
This relatively unknown service only does MSN/Windows Live Messenger, and that too, via a Java applet. This one is also basic, supporting no smileys or colors in the conversation window or even the contact list window, which is devoid of any icons. MSN2Go claims to have HTTP proxy support, which is nice, but this is only important because it’s a Java application. The other services work within the browser, so they automatically take your HTTP proxy. But since it’s so unpopular, you might just be able to get this one working if your office sysadmin has blocked everything else.

MessengerFX
MessengerFX is like Meebo, again, but it only does MSN/Windows Live Messenger. It makes very good use of new web techniques and AJAX, including movable windows and sound alerts. It looks decent enough, but the typography and CSS is a little rough around the edges and there are way too many Google ads all over the pages. They aren’t intrusive, but they’re still littered all over.

The next bunch of clients are original offered by the same people who made the software, not by some third-party users. Naturally, each of them will only support their own messenger.

MSN Web Messenger
This should need no introduction. MSN Web Messenger is the original, official web-based client for MSN Messenger. It looks and feels almost exactly like MSN Messenger 7.x, including all icons, smileys and window trims. The main contact list window pops out on its own, and each conversation window also pops out. But even though the web-based client looks just like the original client, it doesn’t offer features that competing web-based messengers offer, such as being able to right click a user in the contact list for more options (i.e. viewing his or her profile). The other issue with MSN Web Messenger is that, since it’s the official alternative, it’s probably already blocked by your office sysadmin.

Yahoo! Web Messenger
Yeah, it still exists, but it doesn’t seem like there's a lot of work going on over this project – it’s still quite dated and uses Java. It does smileys, but no IMvironments, of course. It looks okay, quite similar to the old clients that didn’t come with a lot of completely unnecessary stuff that the recent versions come with. And what’s funny is that Meebo looks more like Yahoo! Messenger than this original web-based messenger!

To use Yahoo! Web Messenger, visit the Yahoo! Messenger website and find the ‘Launch Web Messenger’ link hidden away around the bottom of the page.

Google Talk in GMail
This is actually the 11th item in this list of top '10' web-based instant messengers, and it’s also the most popular and utilized one, but I didn’t feel it right to include somewhat obscure links like MSN2Go and exclude Google Talk in Gmail.