AUSSIE_ADELAIDE  I have been looking for something which does exactly what this does. Bought a non-apple mp3 player from china, and was finding that I had to delete dot-underscore files for every tune I imported. This does it automatically, and even cleans up files you might have previoulsy brought across. Well done! I just had to find CpMac in my "Developer" files and move a copy to application Support, and I was away. If you don't have developer tools, you'll need CpMac, which is a very small file. *****  
(Version 2.6.1b)

ANONYMOUS  Thanks for developing this excellent program. I just bought a non-iPod Mp3 player (wanted a radio!), which was listed as Mac comptabile. Realized when I tried to put music on it, it dumped extra files (location data?) on the player, which the player then would try to read as a file. After searching the net for hours, I finally stumbled on this program, which really has done the trick. I'm going to spread the word on other boards, cuz I know I'm not the only one with this problem.  
(Version 2.5b)

ANONYMOUS  Actually if you use the cpmac extension KopyMac will preserve resource forks. Also it copies files, leaving the original untouched. Last if you know the creator code/type you can restore them using a resource editor like res-edit or filettyper.   
(Version 2.5b)

MADMAC  Be careful! The ._ files store the corresponding resource fork of (classic style) Mac OS files.

Be sure to tranfer only data files (for example images) without any resources.

Otherwise, you could loose some important informations and there is no way to revert.   
(Version 2.5b)

LOBO  Please let me know if you find any bugs in this beta version of KopyMac.   
(Version 2.2b)