Elon Musk built his fortune starting with Zip2 (sold for $307M, he got $22M) and PayPal (sold for $1.5B, he got $165M). He reinvested this into SpaceX ($100M) and Tesla, where he owns 42% and 12%, respectively. SpaceX is valued at $350B, Tesla at ~$1T in 2025. His net worth, ~$320B, also includes xAI (54%, $50B) and X ($44B buy, now $13.2B). Early gains funded visionary bets that paid off big.