I litterally just puchased an AMD Phenon II quad core, 8GB ram, etc, etc.. for the exact same purpose. I just installad the db software on the first node. and running gentoo. my entire box is brand new and cost under 500$. I also had a cheap dual proc pentium 3 with xen and had an entire RAC system running without issue. (iscsi for shared media over openfiler) It doesn't take much.. not exactly the fastest cluster, but it worked for a test.

..to Blue-Ray? (Why not?)

I am actually in the same boat, however, my son is only 10! He want's to program because it's a big part of what I do.. but, while building stored procedure to traverse billions of records in a database is fun and challenging for me, it's going to bore him to tears.

I've thought about C, but, I think that's a bit to complex for a 10 year old. I'm really excited about Vala, but again, maybe thats a bit much for him still? (again, I want to KEEP him interested) Perl, eh.. easier, but I still fear it wont be interesting enough.

Soo.. my thought. Unreal Tournament. Once you understand program flow, most other languages will become easier to understand. Maybe he gets good at building new weapons, new game types, whatever.. and later says to himself, man, I really wish I had a tool that did this or that. Someone without any background, might not even go there.. but with even a little background he may say, how tough can it be?

anyway.. just my $.02