Jenny's response to the Lightning 11's demand for the Odette II's immediate surrender. First she begins to address the reply as captain, then corrects herself and has it changed to being from Space Yacht Club President. The body of the message is one word: Idiots.
The fact the Club itself pretty much made fools of the hostile ship.
What she says is "Bakame". The "me" particle is extremely rude and hostile, which is why Marika was shocked; it's not something you'd hear a high society girl like Jenny say. A better translation of "bakame" would be something like "You stupid son of a bitch" in terms of impact. Which makes it all the more awesome.
The Crunchyroll subtitles translate it to, "Nuts," as a shout out to a similar real world moment of awesome.
Later in that same episode, when the Lightning 11 begins opening fire on the Odette II, things seem increasingly hopeless. Especially since Odette II doesn't have any weapons or shields, and each shot fired at them comes closer and closer to actually hitting. So what does Marika do? Oh, nothing...she just adjusts the ships solar sails at just the right angle to launch a beam of concentrated sunlight at the Lightning 11, which completely blinds their optical targeting systems and comes close to melting their hull, that's all.
The Bentenmaru's first raid in episode 6 is pretty awesome, especially when the liner's panoramic roof becomes transparent just as the Bentenmaru flies overhead.
In Episode 12, Bentenmaru's boarding party ends up in a Mexican Standoff with Serenity black ops troops, as Gruier and Grunhilde argue heatedly. Tensions rise, and then Marika takes a Renegade interrupt and tosses a flashbang, igniting the firefight, before grabbing Gruier and sedating her... and then when Gruier comes to, she's on the bridge of the ghost ship with Bentenmaru spacers and Serenity black ops cheerfully working together: while Gruier was getting her Latex Spacesuit fitted earlier, Marika contacted the Serenity forces and negotiated a compromise satisfactory to all parties.
Episode 17 almost in it's entirety, especially Jenny's method for getting herself out of an Arranged Marriage, namely shooting her way to a Space Fighter with a pistol she concealed under her wedding dress, and the Big Damn Kisses when she gets to the Bentenmaru.
Episode 18 continues this. Special mention goes to them, taking down Jenny's Evil Uncle while hacking the television stations.
Ai-chan has a moment of awesome at the end of episode 21. With her dinghy's electronics knocked out, she continues with the race by using the stars to navigate. That girl is a born pilot!
Additional points for giving up her chances of winning earlier to help the Bentenmaru shoot down the Bisque Company craft by predicting when the winds would change.
One last thing. To navigate by the stars, you really need a sextant and a good knowledge of the local star charts. Ai doesn't have a sextant, and she only read a book on local constellations that morning. She is navigating by eye and memory.
Points to Marika as well for identifying herself to the attackers to prevent them from shooting down any of the racers and dodging their gunfire, and to the Bentenmaru for risking atmospheric flight.
The Bentenmaru's battle with the Grand Cross at the start of Episode 24.
Episode 25. A group of pirates attempt to assasinate Quartz, the pilot/Captain of the Grand Cross, whom Ironbeard is escorting back to Imperial space. Ironbeard and his men are outnumbered and outgunned... and then Ririka appears and nonlethally neutralises the would-be assassins. She definitely lives up to her name of Blaster Ririka.
In Episode 26, Bentenmaru, Barbarossa and nine other pirate ships go up against Quartz's Grand Cross (three of them) and utterly curb-stomp them.