I'm an instant messaging junkie. Mostly I use the IM in Skype but I can also be seen on the AOL IM platform through iChat. I know lots of folks that also use GoogleTalk, Yahoo's IM offering, and so forth. This means, in general, these folks will have many different IM clients open.

Adium (sounds like a new cholesterol drug) allows you to access many services in a single client rather than having multiple windows open.

Adium does not support video or audio--no calling home on the cheap using it. However the handiness of NOT having multiple applications seems like it might be good.