The New House Dilemma

carambola5 writes: "This morning, I closed on my first house (hooray for low interest rates! w00t for low home prices!). Being a geek, my mind is swimming with ideas on how to make it better. Fortunately, I don't have that pesky voice of moderation preventing me from going wild with upgrades (aka: a wife). My question to Slashdot: what upgrades should I do? Instead of describing my house in detail, just give me ideas that would almost definitely not be pre-installed, such as solar panels, a multi-room and occupant-aware sound system, an honest-to-goodness theater room, etc. For the purposes of imagination, assume resale value doesn't matter. If I get some good ideas, perhaps another Slashdot story will document my accomplishments."