In the previous post, I mentioned about Pidgin. And then now I am using another one, All-in-One Messenger. It is actually a Google Chrome extension, that allows you to use multiple instant messengers in the extension.
The nice part of the All-in-One Messenger is the HipChat. I was using standalone HipChat desktop app, it is resource hungry and very slow. Thus, this All-in-One Messenger really solves my problem by running various messengers.
Yet, the limitation is that I cannot disable an invididual messenger like Hangout or Skype. It can only choose to delete the messenger. I tried sign out, but it will automatically login whenever the All-in-One messenger starts again.