Seeking for pluperfection
Had I the hat that I had had
When I had had a hat
Ah! Then the hat that I had had
Would have to have been that!
And if the hat that I had had
Had had a band of red
Then oft that hat that I had had
Had sat upon my head.
Alas! The hat that I had had
Had had a band although
The band the hat that I had had
Had had had faded so.
No more the hat I had to have
Was mad to have and glad -
I threw away that sad old hat
The hat I had had had.
If the reader so desires, they can find the right places to put the commas in amongst all those 'hads'.