The Gold bar submitted a long time ago, this version, for the new WS system,
has the Mann Co. Logo modelled (not just a normal map).

It takes 100 unusual hats molecular extracts to synthetise one bar!

As the '29.9 pounds australium gold' engravement isn't readable in game, it's turned into an easter egg for the model viewer users

Update: A mod using this ingot, replacing the duellist medal is available !
Grab it here:
http://tf2mods.net/mod.php?id=674
Update: Found a bug on the mod version, it has been fixed. (Bars too bright)