IN probably has the best dialogue. Gotta love GET OUT OF THE WAY, BITCH. Honorable mention to SWR for having just outright odd conversations.
UFO had some good ones with Sanae, though.
Ichirin: "So, you've been collecting the pieces of the flying treasure?"
Sanae: "Wait, treasure? Do you mean those charms with 'P' and 'point' written on them?"