Any ideas how to improve hard seats?

Hi Folks, any ideas on how to improve (soften) the rock hard driver seat?
I do lots of long distance driving and have just done a few hours driving, and my rear end (butt, arse) hurts as if someone kicked it!
It usually takes about two days until I can sit on anything for any prolonged time without pain after a long drive. I know there is not much meat to my butt, and probably thats part of the problem, but I really can't continue like this. If I can't improve the seat I shall have to get rid of this car.
My daughter's tiny 1998 FIAT Seicento has perfect seats, so much more comfortable, but unfortunately they are totally different and wont fit into this car.

Thankful for any suggestions!

Have you tried a pillow or a seat cushion? If you do a quick Amazon search they have a good selection or car seat cushions.

It's true, there's lots of seat cushions out there - I'm sure one of them can help this.

Just don't block the seat-mounted airbags.

Thanks for the suggestions!

I had hoped there might be some sort of other seat part suitable for exchanging, but it doesn't seem so.
The stock seat-bottom is actually a metal pan with some very thin and rather hard foam over it, and the visible cloth on top. The foam is so shallow, its just pathetic, a sick joke.

Today I was carving a piece of foam taken from an old matrass. It will be placed on top of the seat and receive a cover. The same will be done for the passenger side seat. Its better than nothing...

Its pretty easy to remove the seats, and INUVIK stated he has a DIY electric seat heater which means you can disassemble the seat ((too stuff your foam in))

Maybe your best killing 2 birds with 1 stone? I ordered a seat heater kit thru summitracing.com its complete from kit with relay etc just add power and ground your done.

Just haven't got around too it yet. Ive never had a seat apart so maybe this won't work but ide try before dealing with seat covers.

Seat heat is awesome! The seat covers simply unzip and you could place some high density foam in the seat and back and rezip it back up if you desire. As long as it doesn't interfere with the seat airbags you're good to go! But having heated seats really make longer drives so much better.