Just like WoW in-game chat it looks like we will get support for colours in the Diablo 3 chat. A nifty user posted on his blog a guide to how you can change the colour of your chat text in Diablo III. This is not supported by the UI in the game at the moment but I hope we get this at release. It is not only colours that can be changed, but there is support for some icons as well. What stands out is the icon for platinum, does this mean we will get a new higher currency later in an expansion?
If you want to make your text smaller all you do is add
There are some pre-defined colors that are used for in-game tooltips and item rank.
And then we have the icons
Update: Looks like Blizzard already hot patched it. When trying to do this in the US client we get Error: 45 but no error popup in the EU clients.