I'm looking for something like an old-school meccano set - targeted at the more professional/ maker market rather than a toy.
I seem to recall Dave getting something like this one a mailbox; it differed from meccano in being based no metric dimensions and having a triangular (or hex) hole pattern rather than a rectangular pattern.
I was sure I had saved a link and details , but can't find it now I need it, and I've tried search the wiki and google without finding it; but I'm probably not using good search terms.
I think iha da name ending in 'otics' but that really a guess; although quite frankly any similar product would do.