Erm, no, but only because I've got nearly every tool known to man for general gardening already, so I just use those. There is already a system available of a handle with different attachments, though I can't swear they do short handled versions for container gardening.

Certainly not for indoors.....

The tool you are describing, Clare, sounds as if it would fit well into one of those catalogues that occaisionally drop through the door; loads and loads of 'potentially useful' gadgets at very high prices. Presumably, some people do buy from these catalogues, otherwise they would stop producing them - not me however. Sorry, Clair, I would not be one of your customers.

For the sake of your Alevel project Claire, if you haven't realised yet, outdoor and indoor gardeners are slightly different breeds. There isn't really a need for tools for indoor gardening, beyond a spraybottle and maybe a trowel and hand fork for larger planters and window boxes. As Bulbaholic says what you're describing can almost certainly be found in the insert magazines.
The only thing I'd add to the list is a long-spout watering can for the pots that can't be plunged into a bowl of water. Though I'm sure there are plenty of people out there who have perfectly designed, well-clleaned and polished sets of tools in their conservatories for their friends to see.

Ok thank you