I have a long list of other creative projects which are either ongoing or which exist in embryo and I'd like to work on properly at some point, including:
- The sort-of-slipstream-fantasy novel I've mentioned writing at various points over the past year (due a rewrite and polish once Tales is out of the way);
- An illustrated anthology of @trapphic stories (which I'm trying to think of a less awful name for than The Volume of Trapphic);
- A collection of my Christmas stories (which ideally needs 24 pieces in Advent calendar format, so either I'm going to have to write more than one a year or it'll have to wait until I'm 60ish;
- Some ideas for other anthologies I'd like to edit if this one comes off, both in the City of the Saved and outside it;
- Speculative story ideas for potential future Faction Paradox, Iris Wildthyme or Señor 105 anthologies from Obverse Books;
- A quartet of more or less SFish novels which I had planned out in detail and was working on before I decided to write the other novel instead, and which at present go by the working titles A Giant in the Earth, The Air of Utopia, The Knowledge of Fire and By the Waters of Albion;
- A non-genre novel I wrote a chapter of years ago called Fragile Monsters, which I'd kind of like to spend more time on at some point.
In fact, the Doctor Who proposal (then called A Memory of Fire) had a somewhat epic history: conceived as a seventh Doctor story unreliably narrated by the eighth Doctor (who would have been doing his best to conceal a piece of treacherous duplicity by his past self), it went through a number of permutations at BBC Books' behest, including an eighth Doctor novel in which the original narrative appeared as a flashback, a fifth Doctor novel narrated by the sixth Doctor and the original idea presented as a short story (this was shortly before the BBC stopped publishing Doctor Who short story collections), before they finally rejected it. Since I hadn't at this point been published professionally at all, their interest was encouraging as well as frustrating.
Eventually, at BBC Books' recommendation, I submitted it to Telos Publishing instead (this was shortly before they stopped publishing Doctor Who novellas) and on the back of it was commissioned to write Peculiar Lives, with which it shares nothing whatsoever except a narrator who ends up somewhat regretting his past actions.
I still have these variorum proposals, including three variant plots, two variant prose samples, the complete 4,000-word short story ("Faith Healer"), and an explanatory note outlining the relevance of the theories of Carl Jung and Rupert Sheldrake. The only thing that's stopping me putting the whole lot on the web is a) the hope that one day I'll use some of the most striking concepts (specifically, two posthuman species called the Orpheids and the Dhebeth) in The Knowledge of Fire, and b) the same lack-of-time issue which has prevented me putting online the outline of my abandoned Prisoner novel Island in the Ashes and my proposal for a pulp-steampunk novel, The Curse of Odin-Hotep, whose sample chapter I did once post to this blog.
By contrast, everything on the list is stuff I'd like to get around to doing some day, when time and energy allow. So possibly when the two-year-old has turned eighteen.
 The "air" novel is also based on a rejected Who proposal (Unearthing the Princess), as are elements of Of the City of the Saved... (Sabaoth) and Nobody's Children (Relativity, or Baby Rachel and the Sexually Dimorphic Punk Polecats from Outer Space). I submitted rather a lot of these.
 Who I passionately dislike, so I was rather relieved when they didn't want to use that one.
 It's actually slightly more complicated than this. The original novel proposal, the short story and the novella proposal -- though not the other variants nor my still-intended The Knowledge of Fire -- incorporate elements which I developed for my earliest Doctor Who novel proposal, Word Perfect, submitted to Virgin Books circa 1995, and which derived ultimately from The Space Monastery, a script I sent in to the Doctor Who production office in 1987 when I was 15. None of this is stuff I still intend to use, though. Especially The Space Monastery.