Doctor: Sonic blaster, 51st century. Weapon factories of Villengard?

Jack Harkness: You’ve been to the factories?

Doctor: Once.

Jack Harkness: They’re gone now, destroyed. Main reactor went critical, vaporized the lot.

Doctor: Like I said. Once. There’s a banana grove there now. I like bananas. Bananas are good.

From Doctor Who – Season 1 Episode 10: ‘The Doctor Dances’ (1×10)