[texhax] diagonal in a table

[Robin Fairbairns]

> Do you know a correct way to typeset the diagonal line in the upper left
> cell of a table like this:
> 
>  --------------------------
>  |\ k |    |    |
>  | \  |  1 |  2 |
>  |n \ |    |    |
>  ----------------
>  |    |    |    |
>  | 1  |    |    |
>  |    |    |    |
>  ----------------
>  |    |    |
>  | 2  |    |
>  |    |    |
>  --------------   ?

the slashbox package does this.  since i've never used it, i can't say
more than this.  (what's more, i've never got around to writing the
obvious faq answer.  it's on my list, along with one for multirow.)