Shoutbox

is there a script or something which lets you put your own font onto your display name?

You can make that with both, skins and scripts, but that change would apply only for your windows.

The only thing you can do is use different characters to make it appear different, for example à è ï ô û, etc. As robert_dll said, you could force Messenger to use another font, but only you would see that, not your contacts.