Clark sees an original copy of Friedrich Nietzsche's Beyond Good and Evil in Lionel's safe. This is the third appearance of Nietzsche in the series. Clark was holding "The Portable Nietzsche" in Pilot, shortly before Lana asks him, "So what are you: Man or Superman?". In Suspect, Lionel is shown reading the same copy of Beyond Good and Evil.
Clark finds a message from Lionel in his LuthorCorp safe. There is a Kryptonian message on it that Clark translates out loud as, "For Kal-El in the event of my death." The actual written message in Kryptonian translates as, "For The Tarveler" (presumably, a misspelling of "Traveler").
The last words of Lex for Lionel were: "No one will remember your name." This is perhaps a reference of the comics where Lex's father doesn't play a important role and is only occasionally seen or mentioned.