Uses for a Linux server

Hey guys! I just scored a free PC, its a 2.6ghz single core with 1GB of RAM and a 40GB SATA drive. What on earth should I do with it? I already have a web server, a DNS server, and pfsense as my router. I've also got a Zabbix server monitoring system partially set up in a VM on my Proxmox server, along with several game servers. I'm out of ideas, what should I use this for?

I'm up for a challenge just FYI

A bathroom email checker...

This is oh so good. Have your own web services: 

https://yunohost.org/

Encrypt your email:

https://www.mailpile.is/

There is always freenas but you said linux

http://www.openmediavault.org/?page_id=1562

Have a hardware fire wall and VPN:

http://www.clearfoundation.com/Software/overview.html

Yunohost actually looks really cool! I can't believe I've never seen that before. I've heard of mailpile, but I forgot about it till now. As much fun as it would be I don't really need a NAS, my only client machine is my laptop so I don't need to share files. I have a hardware firewall and VPN set up through pfsense on a crappy ITX machine.

I will definitely be giving Yunohost a try. I think this is going to become my quirky fun server (I've been pretty tight with what I do to the other bare metal OSes) and maybe I'll do some cool stuff with it. I'm buying a UPS soon so maybe make it play a song when the UPS goes to battery. Maybe even make it beep the Mario theme when it boots.

Thanks guys, keep the ideas coming!

Blow it up. Nothing more to be said.

How does self-hosting work? I was considering it before but then I saw that most home internet plans do not allow it. All you need is a domain and then you can direct it to your server right?

You just point a domain to your public IP address, and then forward port 80 (or whatever port your application uses) to the server(s). Its not terribly hard to host websites but email hosting is a different story. You will need to keep the server machine on all the time though. Plus you have to keep the machine secured against any exploits in its software. Its good if you know what you're doing but for an important site shared hosting is better.

If you aren't doing any high traffic stuff most ISPs won't notice but when I comes to Email it does get blocked by spam filters prettying ten if it is on an Public IP address 

Yeah honestly we're the least of their worries. I haven't tried email but I have a pfsense VPN set up and my friend is on it almost 24/7, plus a web server and a handful of game servers, and I've never gotten a complaint from them. I'm sure if I started hosting 4k movies on the web server they'd be pissed but for what I'm doing MediaCrap is more preoccupied with fixing their terrible infrastructure than with yelling at me.