1. I'd pay the folks at the Genode project whatever it took to produce a live CD bootable image, and keep them doing it with every new release. (genode.org if you care)
2. I'd see if the silly idea I had in college for an FPGA replacement on steroids would actually work by designing the chip and having it fabbed... then fixing the bugs until it worked right. (bitgrid.blogspot.com if you care)
3. I'd redo the house, install enough solar to power everything, and build a laboratory with a machine shop.
4. I'd build my own locomotive to run out at the Heston Steam Museum (either diesel electric, or just electric)
4. I'd dig to the bottom of the cold fusion thing, and see if it really works.