AndExplorer is a file manager for Android devices. It allows browsing files and folders stored on device and sdcard. It can sort by name, size and date. Rename, delete, create folder features are available. It is able to uncompress ZIP, GZIP and TAR files too. It can be called from another application through Intent facilities.
Using the Terminal Emulator program, if I switch to /data and execute the "ls" command, I get a permission denied error, but if I type "su" first, then "ls" works and I can see the files in that directory.