Time Roaches were nesting creatures from the Vortex that were attracted by radiation that leaked into the Space Time Continuum. They took refuge in engines, where they could cause much trouble and disruption. (COMIC: Rough Waters)
A Time Roach once tried to feed on The Doctor's TARDIS while it was travelling in the vortex. The Eighth Doctor set a trap for it, however it managed to escape into 20th century Scotland, where he and Charlotte Pollard encountered lieutenant Mike Yates. The three of them managed to stop the roach, however, and reversed any damage it had done. (AUDIO: Foreshadowing)
An infestation aboard an aircraft carrier in the 21st century took the carrier back in time two hundred years and dropped it in the middle of the Battle of Trafalgar (21 October 1805). Sailors at the time believed it to be a metal sea monster (maybe a Kraken) that appeared from out of a fog. (COMIC: Rough Waters)