awesome Felix....just AWESOME!!
like 7shades' rule, i have a similar rule i follow, specific to not keeping left....called the 5 second rule.
if a car is in the far right hand lane when there is ample room around it that it could safely move into the left lane immediately next to it, and i happen to be in the right lane immediately behind it, i start counting to 5. i do it slowly, so it would take between 8-15 seconds to get to 5. once 5 is reached, i undertake them (which is illegal AFAIK in VIC if the road has a limit of 80km/h or above, but haven't been able to find the secion in the Vic Road Rules Law) while abusing them and honking. what happens from there is always a mystery.
it's worked well for me, so far anyway. will be getting some hand held signs so my co-driver can hold them up for the offending driver to read if we're stuck behind them in the right lane, and for when we're passing them on the left. just so they know that they're doing the wrong thing and that they should perhaps re-read the road rules before they next go on a drive.