MSN? iChat? What program?

I saw a screenshot of Mac OS X (which I now can't find to show you) and it hasd a transparent type contact list from a messaging program running which looked like MSN - I know it's a bit of a long shot without a screenshot but does anyone have any idea what program this might be?

I have MSN but the contact list isn't transparent - it's much like the Windows one.

I have AdiumX and the contact list can be made transparent...could be that....

You can see the transparant list at this link:

http://www.deviantart.com/deviation/38617991/