I noticed that samba mounter can see my Winodws machines, even they are not configured to samba.
Today it doesn't work anymore. 
All my amigas says that they can't reach some nonsense IPs, when I try to open my NAS/Projects folder.
The Windows setups I have seen use DHCP to dynamically get their IP address. After this lease time is up, DHCP will request another address which may not be the same as the first time. If the IP address changes, any attempts to use the old address will give errors. The Windows network connection needs to be configured to use a static address (for your side of the router/DSL box only). If you look at the old Amiga configuration and can figure out what the old IP address was for Windows, then you can enter it for the static IP address in Windows and you will be able to access it again. Doing all this is not trivial and varies from one version of Windows to another. It's possible to mess up your working internet config so be sure to record current settings before you change anything.
You can't use Samba for Linux. Samba is only to connect a non-Windows Computer to a Windows Network.
Samba was developed on Unix:
http://en.wikipedia.org/wiki/Samba_%28software%29My Linux install came with SAMBA already installed in an SMB directory. Unfortunatly, I was not able to get it talking to my Amiga's SMBFS due to the high security and complex configuration (despite being able to see everything).
