Since the launch of rFactor 2005 some people have created external HUD's for rFactor. Some are working good, some worked good but stopped working with the latest rFactor patch for some reason, others had other problems, some show very much information, others only some basic information.
With rF-SkinHud you are able to create your own customized external HUD. This way you can put just the information you want on the HUD and make it look any way you want. The only things you need is are text-editor (even notepad will do) and a drawing program (photoshop, gimp, but even mspaint is sufficent).
You can use rF-SkinHud on a second monitor or on a networked Windows or Linux pc. You can also use a PDA by the use of a tool called sidewindow.