What should I build i'm minecraft? I need ideas?

A while ago a friend and I started a world on minecraft that we just kept adding to. We now have a high rise, a indoor pool, a complex whit several buildings, and a greenhouse. I need new ideas of things to build in this world to make it even bigger and cooler than it allready is. Anything helps, Thanks!

I'm looking for a computer?

Ok well my price limit is 320
All I want to do is run minecraft
Where or what is the best laptop for that price

I have a HP Compaq (refurbished)?

I would like to upgrade my cpu and gpu so i can play games smoother and render faster on sony vegas. I was thinking about getting the Intel Pentium E6800 cpu but i'm not sure whether it's worth it. Since it doesn't come with a built-in gpu, I was wondering which one to get that will fit inside my pc. Most gpu's are too big. Can someone please suggest a decent one I should get and whether that cpu is a good combination? The main reason for upgrading is to play Amnesia, Minecraft and to render faster in Sony Vegas Pro 11. Right now it takes 12 hours to render a 12 minute video. I can play minecraft ok but it's farely laggy. I can't play Amnesia at all which is a shame because I would love to play it.
Any help would be greatly appreciated, thanks.

My PC Specs:
Intel Pentium D 945g cpu 3.00 GHz Dual Core
4GB Ram
80GB Hdd
32 Bit operating System
Windows 7

Any real proof on herobrine?

Okay so i've been playing minecraft for years with no multiplayer and i've seen mc steve around but with white eyes so i looked around the internet and herobrine popped up so my question is… Do i have a minecraft stalker

Best minecraft house tutorials?

I'm looking for a house tutorial on minecraft and I need some good YOUTUBE tutorials.

Please no easy ten minute houses; I'm looking for a BIG HOUSE, MANSION, OR CASTLE tutorial that looks really huge and awesome, and takes a while to make. Only YouTube videos please.

Should i get mincraft on the house pc or my brthers pc?

Okay so i really want to get minecraft pc version and i said i would pay but i'm not sure if i should get it on my brthers pc because its fast but he will be moving out in like a year or my house computer but its super slow and laggy and we could be getting a new one but not next year