I've been happily using Yahoo Messenger for quite a while, but the
newest version (which I have to use) has a ridiculous window size. The
program itself does not allow you to resize the window of the
messenger itself to smaller then about 300x150 pixels (guesstimate).

There should be a utility out there that will allow me to manipulate
window attritubes regardless of what the application itself wants;
I've used this about 8 years ago but cannot find it anymore.

Can anyone tell me where I can either:
1/ find the utility to manipulate the size of the Yahoo
Messenger-application to something less megalomaniac, or:
2/ find another way of resizing the Yahoo Messenger-application window?

Thanks in advance.

I found a little patch program that allows you to resize the yahoo
messenger window down to as small as just the window header bar
showing. Its a fantastic program.

You can get it here.
http://downloads.elitenick.com/pafiledb.php?action=file&id=934

As with any third party program. Use at your own risk. I have had no
problems with it but that doesnt mean you wont. Hope this helps you.

Thank you! Version restricted though.. I hope I can still download the
version of Yahoo 6 this is applicable for.

I've been able to find an updated version of the patch at 
http://coolyahoo.streamlinetrial.co.uk/members/pafiledb/pafiledb.php?action=file&id=24

this allowed me to modify the window size of Yahoo 6,0,0,1750. Hurrah!