INSIGHT-Mega-IPO to rekindle the 'bromance' behind Alibaba's rise

BEIJING, Aug 28 (Reuters) - Masayoshi Son's nose for an investment has turned a $20 million start-up punt on Alibaba into a stake worth maybe $50 billion or more as the Chinese e-commerce giant co-founded and led by Jack Ma heads to what could be the biggest U.S. tech IPO of all time.