Any new tips for cleaning the running boards?

[eyeguy]

OK I agree the running boards are unnecessary on the X5 and yes I have to be careful not get my pants dirty climbing in and out. But they just look cool...

So what about the water stains? I've read posts about trouble keeping the boards clean. Somebody painted theirs. Anyone find a good product to protect and prevent the ugly water stains or a foolproof cleaning technique? Mildly abrasive cleansers, scotchbrite sponges, etc.

I've read posts from lots of people recently who bought and installed their running boards themselves.

What are you doing to keep 'em clean? Please share. THANKS-