Apologies in advance for total vagueness of this post.

Ages ago I had some stuff that came in a wee container and it was all goopy and it was really good at cleaning keyboards and things.
You just sort of pressed and rolled it all over the surface and it cleaned as it went, then you just put it back in the container. Except I lost mine.
It was also just fun to play with. 
I cant remember what it was called but I think it was a bright yellow/green colour.

Anyhow, I'd quite like to get more of it if it still exists.