Spec, what are your thoughts on this... If I want, I can mail a PC to my shell host and they'll hook it up to the internet for me, so I would be able to have my own dedicated server but instead using their service. Good idea y/n?
Depends on a lot of things. Like Bobbias said, make sure you know what happens if something breaks. If your host is physically close to you, you could probably get physical access to the box. If not, you might have to get it shipped back and forth, which could potentially be expensive (shipping rates) and may be damaging (to the system itself).
On the other hand, you're going to have a lot more of control over the service and probably a much faster Internet connection than if you try to host at home. If you want to seriously upgrade The Tree's services, that's the way to go.
Of course you're probably going to want to fit it with Linux/BSD before you ship it out, make sure SSH is enabled so you can still talk to the thing, etc. No worries about licensing that way. Regardless of which OS you choose, make sure to configure a restrictive firewall, only letting through the necessary services. I could try to help you get ipchains set up if you decide to go with Linux (I have an ipchains-based router set up in Maryland -- our Linksys "router" literally only works as a wireless access point and a switch
); I'm not entirely sure what kind of solution BSD uses (ipfw?).
Also, make sure that whatever system you choose makes it easy to install updates on the box. You definitely don't want to get knocked down due to security problems.
Regardless of the potential issues, I'm kind of inclined to say "hell yes" to the dedicated server idea so long as their policies are tolerable. You're going to have a ton of control if you do that.