An account for billionaire Eli Broad, however, countered Cuban's argumentâ¿¿at least for the super rich."Nothing can get you into more trouble than dabbling in the market," read a tweet from Twitter account @UnreasonableEli. "You would be surprised how few billionaires do much day-to-day investing. Follow a Twitter list curated by Forbes of the world's billionaires here. Follow me on Twitter (and read my tweets about Facebook) at @RMac18.