[TYPO3] Repeating FCEs in columnar (down-across) table

[Peter B]

Ok, here's a tricky one;

I've been given a requirement to reproduce a variable-length list in a 
column based table rather than in a row-based table (i.e. down then 
across) in 3 columns. Each list item consits of several elements grouped 
to gether, so this initially appears to be classic repeating fce.

However, given 10 fces in the container, it should render as:

   01   05   09
   02   06   10
   03   07
   04   08

Given 9 fces, it should render as:

   01   04   07
   02   05   08
   03   06   09

I've produced many repeating fces and menus in tabular form using 
variations on tables, spans, divs, wrap and optionsplit, but always 
across then down. However, this has me completely stumped - is it even 
possible in typoscript?

To produce this using either divs/spans or a table, the sequence of fces 
needs to change according to the number of items. In the first instance 
it would be:

01 05 09 02 06 10 03 07 04 08

In the second

01 04 07 02 05 08 03 06 09

The extra sting in the tail is that in the first sequence, rows 2 and 3 
are only 2 columns wide, so optionsplit can't easily be used to define 
begin/end of row.

Anyone any ideas or am I heading for a userfunc?

Peter.