MSN Money - 7 IPOs to watch even after they go public: "Two recent examples: Tower Group (TWGP, news, msgs), an insurance company where Chief Executive Michael Lee purchased $2 million worth of stock at $8.50 on Oct. 26. And U.S. Shipping Partners (USS, news, msgs), where insiders bought over $1 million for around $23 on Nov. 3 and 4."