Got an Android phone? Got contacts on AOL Instant Messenger, or chatty friends on Facebook? AIM now has an official chat client in the Android Market, one that can run in the background and connect to Facebook and Twitter too.
There's not all that much more to say about AIM for Android — it asks for your login credentials, and if you head into the settings, you can feed it your Facebook login as well, and it will send and accept chats across both fronts. If you want, AIM can hit you with your friends' status updates, update your own at the same time as your AIM status message, and even post to Twitter, too — though there are certainly better dedicated clients for that purpose.
It's likely the most guaranteed means of keeping a connection across AIM's servers, and since AIM can run silently and ping you on new messages, it makes good sense as an Android app.
AIM for Android is a free download for Android phones only. AIM's product page hasn't updated to announce it yet, but should soon.