Today we had talked about Finding disk spaces and here is one for your windows mobile smartphone. Tree Size Mobile is a .net framework based application, displays file system in a tree view and size of folders including sub folders like the softwares which worked on the computer.
I wasnt able to test it out this is useful if you often run out of space on your windows mobile. Moreover this is a free product with a size of 187KB. This supports WinMo 6.0 and should work for high version. Download Tree Size Mobile