<p>Is there a way to mount a Linux directory from a different PC to your local Linux PC? How?</p>

You need to be a bit more specific.  You can use NFS.
Depending on what distro you're using, you simply edit the
```
/etc/exports
```
file on the remote machine to export the directories you want, then start your NFS daemon.
Then on the local PC, you mount it using the following command:
```
```
mount -t nfs {remote_pc_address}:/remote/dir /some/local/dir
```
```
Use the
```
man
```
utility for more information:
man exports
(Examples of configuring directories for export are on the bottom of this manual page.)