Swiss File Knife

The Swiss File Knife is a multi-function command line tool, designed to avoid the need to install many other small tools. With SFK, you can instantly

- find and extract text in binary files
- list dir tree sizes
- filter and replace text
- run an instant ftp server
- find duplicate files
- join many text files into one
- create and verify md5 checksum lists
- run a self-defined command on many files
- remove TAB characters from text
- create hexdumps from files
- find dependencies between files
- print colored text to terminal
- locate commands within path
- print last lines of a file
- convert hex to binary
- convert binary to source code
- convert CR/LF line endings
- split and join large files
and further functions.

no installation, and fully open source.

downloads are available here
http://sourceforge.net/project/showfiles.php?group_id=160478

and further documentation under
http://stahlworks.com/dev/swiss-file-knife.html

binaries are provided for win98 and later, as well as linux (for older versions like damned small linux, and newer ones)

i'm not sure if a command line tool matches the general concept of PortableApps; nevertheless, i wanted to mention it.