Memory starts ok then goes through the roof.

This may be an old chestnut , but does anyone know why my IconX memory usage starts off nicely at 18,000 k , but shortly after starts clinbing up.It might sit at 99,000 for a while but eventually gets to 130,000 k plus



Any help with this would be much appreciated, I really need all my 3gigs of ram, and I can't imagine going back to the old desktop.
I will except hugs, this time-