Heroes Season 4 Episode 8

Hiro: Oh, boy!
This is the famous catchphrase of another well-known time traveler, Sam Beckett, from the 90's TV series Quantum Leap. Sam would say these two words, with differing amounts of emphasis at the end of the teaser for each episode after he realized what body and situation he had leapt into.

Hiro: It's Mothra.
Referencing the giant moth-like Japanese monster first seen in the 1961 movie Mothra. The monster is occasionally seen as a mammoth egg, which hatches into a giant web-shooting larva, and eventually matures into the familiar moth-like form. Originally she could generate gale-force winds and lift other monsters into the air. Later in the 90s, she was given additional powers to fire energy beams from her antenna and generate electricity.

Hiro: The MJ to my Spidey.
Referencing Mary Jane Watson and Peter Parker, aka Spider-Man. The couple have an on-again/off-again romantic relationship in the comics. MJ eventually learns Peter's secret identity, they marry, and later become separated through supernatural means. The relationship is a major plotline in the three Spider-Man movies, as well as the animated adaptations.

Past-Hiro: The Marle to my Crono!
Referencing the console role-playing game Chrono Trigger. The protagonists, female and male respectively, are two of the three playable characters from the game setting's 1000 A.D. setting. The Nintendo DS and Playstation games show the couple marrying in a final scene at the end. Crono is killed in the game but, like Charlie here, is saved through the use of time travel.

Noah: "Now, fair Hippolyta, our nuptial hour draws on apace; four happy days bring in another moo:; but, o, methinks, how slow this old moon wanes! She lingers my desires..."
Referencing Theseus' line from A Midsummer Night's Dream, Act 1, Scene 1, addressed to his wife-to-be Hippolyta