Yahoo messenger is huge:

And that's as short as you can make it, it won't shrink vertically anymore.

How can i make it a more reasonable size, e.g.:

In fact, if we're making it look better, how about Yahoo stops pissing on their users and makes it:

Okay, yes, the last one was me complaining. But the first two are a valid question!

Note: The cut-off title bar is because Yahoo! developers don't pay their taxes, and assume that everyone runs at 96dpi.