AndyRenamer
AndyRenamer is the sofware to do batch rename, that can save your time for renaming many files.
It will remember the last number of files. If source dir and target are difference, will copy and rename.

BitsInside Explorer
BitsInside Explorer is a fully featured file manager / explorer for Pocket PC's.

FileCommander
Freeware file manager with ftp and telnet support. Bonus game ( "Lines") included. Requirements: PocketPC, PocketPC 2002 StrongARM, MIPS, SH3

GSFinder+
GSFinder+ is a great File Manager and a perfect replacement for the default Windows CE/PocketPC File Explorer. GSFinder was first created by Y. Nagamidori as an open source application. GSFinder+ is an advanced version of GSFinder made by M.Toda introducing some new features like ZIP and LHA archives management, Drag-and-Drop, and network options.

myExtensions
myExtensions is a utility that lets you modify and create file associations. Add, edit, copy or delete registered filetypes on your PocketPC with ease!

Total Commander
Total Commander is a file manager, a program like Windows Explorer to copy, move or delete files. However, Total Commander can do much more than Explorer, e.g. pack and unpack files, access ftp servers, compare files by content, etc!