Ianto is a time lord
I've forgotten the author and title, and where I'd saved it so I'm hoping this is familiar to someone. It's discovered that Ianto is now a time lord (this may be after Ianto had been hurt or killed but I'm not sure about that) with 2 hearts. His new existence is noted and a swarm of some sort of robot creatures show up to kill him and the Doctor, who'd also sensed him. Ianto's TARDIS is disguised as children's play equipment in a nearby park (a dome-shaped jungle gym?)