Suggestions for a home IT strategy, please

I am looking for - sad though it may sound - a bit of an IT strategy at home. I host my own website(s), need VPN access to data on the servers, prefer routing with a dedicated server OS rather than a "hardware outer", want centralised storage of all my media, potentially like the idea of thin clients or LTSP clients for my 'media nodes' or Linux MCE running on cheap boxes in each room.

At my disposal I have:

• Apple G4 Quicksilver running OSX server - hosting and routing and VPNing at present - with a lovely quad NIC in it
• Old Sun Sparcstation
• Very old beige box Mac
• Shuttle PC with 1000Mhz Celeron
• Dell GX620 dual core beast (can't remember how fast, some kinda geek, huh?)
• Dell GX280 HT doodah that makes another nice desktop
• Horrible BT Homehub that I would love to dump. It only interfaces ADSL with Ethernet at the moment, everything else is handled elsewhere.
• Cash to spend on various additions to get what I want, although by no means a limitless pot.

I also harbour some mental desire to set up Asterisk for VoIP instead of the stupid BT offering, but I reckon that's the least of my project worries right now. What recommendations can anyone shout at me at how to use what I have to do what I want, avoiding spending all the cash I have and more. Or, in other words, what do you all play with at home that makes you happy? Fanboys need not apply and only sensible well rounded answers will be of any real use. Feel free to suggest junking things if you think I'm wasting my time with them!