You may have noticed that MSN Messenger looks pretty drab next to Yahoo's. Nothing in the preferences to select anything but the faded chess pawns. Why pawns, you ask? Because we, the users, are the pawns in Microsoft's game, and they're cocky enough to tell us so.
Still, it's easy enough to give it a background pic of your choice. Just open the directory \program files\messenger where they insist on installing it without asking whether we want it there. Rename the file 'lvback.gif' to 'lvback.old' (or whatever you like). Copy a new pic to the directory, in the gif format, naming it 'lvback.gif'. Also save your pic there under a descriptive name, because whenever MSN installs a new version, it will over-write lvback.gif as the same old pawns, so you'll have to repeat the proceedure.