How can I make a file un-hidden permanently?

Solution 1:

In Terminal defaults write com.apple.finder AppleShowAllFiles TRUE, relaunch Finder. After that you'll see all your hidden files in Finder.

Now type

chflags nohidden

into Terminal and just drag&drop file that you want to unhide on the line. Enter.

defaults write com.apple.finder AppleShowAllFiles FALSE will reverse Finder back to normal.