How about taking ten years and building a fully functional Lamborghini Countach replica in your basement.
From Jalopnik:
Hand-Made Lamborghini Built In Basement Finally Sees Light Of Day
Seventeen years ago, Ken Imhoff watched Cannonball Run and became so enamored with the Lamborghini Countach in the film, he hand-built his own, in his basement. In what we imagine might be the most Jalopnik build ever undertaken, Ken designed and fabricated his own tig-welded frame, installed a thoroughly massaged 351 cubic inch V8 with a ZF-25 5-speed transmission, hand-formed the aluminum body over a meticulously measured and accurate body form, and finished it all off in a beautiful metallic gray. It took Ken 10 years to complete the project, and the results - as you can see both in the gallery and in the video below the jump - are amazing. There's only one problem, when you build a car in a basement - how do you get it out?
Ken had to hire a contractor to dig down to the basement wall, cut through it and build a ramp to pull the car out.
Amazing story and a lot of very cool photos at the Jalopnik site...
Ken's home page is here: KIEngineering
