`recode' is a great utility on Ubuntu if you need to share a Ubuntu file with another OS (don't tell about dos2unix and back).

First install recode:
Code:
sudo apt-get install recode
`recode' needs to be used at the console.

Sample usages:
Code:
recode ..pc <file>
Convert the UNIX-style <file> to DOS/Windows format.
Code:
recode mac <file>
Convert the Machintosh-style file to UNIX (Linux, BSD etc.) format.

Simple tutorial on Usage
Code:
recode
The command.
Code:
<format>
The format. By default, convert <format>-style file to UNIX-style format. Use .. for the reserve.
Code:
<file>
The file to convert.

Enjoy!