Software for Linux Home Server

I recently built a Linux based home server and would like to know some programs that are "essential" for such builds. Granted I have some things in place at the moment and have others I am planning but I want to make sure I am not missing out on something. Also if you could give me some direction on these things it would be very helpful.

Hardware:
- i3-2120T
- 8GB RAM
- 2x 2TB WD Green HDD
- BD Drive
- TV Tuner

Software (done):
- Software RAID1 with mdadm
- Install of Xubuntu 11.10 alternative 64-bit
- Setup Samba for "in-network"
- Setup SSH and SFTP for "out of network"
- Wrote simple bash scripts to start, stop, & restart Samba, SSH, SFTP

Software (to-do list):
- Limit SFTP directory to that of the Samba directory
- Setup something (probably VLC) to watch DVD's and BlueRays
- Get the TV Tuner working. Recommended programs anyone? (MythTV didn't want to work for me last time)
- Get a Craftbukkit Minecraft server setup for a small group of friends
- Make a "panic" bash script to safely close programs and shutdown
- Batch script to do periodic data backup to server maybe?

Software (sounds interested but I know nothing about):
- Setting up a website.
- Setting up a private wiki.
- Proxy server
- Firewall