Currently up for bidding on Ebay are two promotional Mega Man hats from an old Consumer Electronics Show (CES), distributed only to attendees. Based on the hats' logo, I assume they might have come from CES 1989 where Mega Man 3 was featured. Yes, that CES.
Two colors are available, orange and pink, both never worn. I imagine they'd make for neat collector's item if you're into rare promo goods. Click the above respective links to bid!