How can I use NTFS partitions in OS X? My coworkers use NTFS partitions, and I can't share my data with them, as NTFS on Mac OS X is read-only.

How can I read and write onto NTFS partitions?
For free, you can use the NTFS-3G driver. In order to use it, you have to install MacFUSE first.

In the end, you'll have a prefpane to mount and manage your NTFS drives