Listing some projects....

If you want to simulate some (wired or wireless) Network you can read and use this projects:

1) Network simulator NS2
http://www.isi.edu/nsnam/ns/

2) OPNET (You have to be registered)
http://www.opnet.com/university_program/itguru_academic_edition/

If you want to Monitor and Manage small/big networks you can install:

3) CACTI
http://cacti.net/

4) NAGIOS
http://www.nagios.org/

5)NTOP
http://www.ntop.org/

And if you are looking for the best Linux based operative system, stop and go to:

6)UBUNTU (I recommend 7.10 Server Version)
http://www.ubuntu.com/


Cooming soon I'll post some tutorials and HOWTOs....